Molex Micro-Fit 3.0 (MX3.0) Connector Complete Guide: the Two Force Pairs That Are the Original’s Own Numbers, a 250V Rating Against a 600V Family & the KONNRA KR3000 Equivalent

Quick answer: The Molex Micro-Fit 3.0 — sold and catalogued in Asia as MX3.0, and formally the Micro-Fit 3.00mm (.118 inch) centerline crimp connector system — is a 3.00mm pitch, single-row and dual-row crimp family that does both wire-to-board and wire-to-wire, holds by a positive friction lock with an optional terminal position assurance (TPA) device, and is rated by Molex at 600V, up to 10.5A, from −40 to +105°C with tin plating or −40 to +125°C with gold, in 2 to 24 circuits. The KONNRA KR3000 is the cross-reference equivalent, and this is the round in this comparison series where the mechanical layer lines up most closely: Molex publishes a 14.7N maximum contact insertion force and a 24.5N minimum contact retention force, and our product specification publishes 1.5kgf (14.7N) maximum and 2.5kgf (24.5N) minimum — the same two numbers, in a different unit. At the connector level Molex publishes 8N maximum insertion and 2.4N minimum withdrawal per circuit, and our per-circuit ladder gives 0.80kgf (7.85N) and 0.25kgf (2.45N) — a window that sits inside the original’s own window at both ends. Four other rows also match exactly: contact resistance 10mΩ maximum, insulation resistance 1,000MΩ minimum measured at 500VDC, durability 30 mating cycles, and humidity 96 hours at 40°C and 90–95% R.H. Where we are genuinely behind is voltage — 250V published against the original’s 600V agency rating — and the wire window, which covers three of the seven conductor sizes in the original’s own derating table.

I work on connector and harness programmes at KONNRA, so treat the disclosure as read. Everything below comes from manufacturer documents on both sides, and where they disagree I have said so rather than averaged. That applies to the original as well as to us: Molex’s own test summary reports 19.95mΩ of contact resistance against Molex’s own 10mΩ limit, and Molex publishes two different minimum pull-out figures for 24 AWG wire in two different documents. Both are printed here rather than tidied away.

KONNRA KR3000 series Micro-Fit 3.0 3.00mm wire-to-board crimp connector

👉 KR3000 Series product page · Wire-to-board version · Wire-to-wire version

What the Molex Micro-Fit 3.0 Actually Is

Micro-Fit is one of Molex’s largest connector families, and the first thing to understand is that it is not one connector — it is a family of product lines built on a shared 3.00mm contact system. Molex’s own scope statement for the dual-row product specification reads: “This Product Specification covers the performance requirements and test methods for Micro-Fit 3.00 mm (.118 in) centerline (pitch) wire to board and wire to wire connector systems terminated with 18 to 30 AWG stranded copper wire using crimp technology with Tin or Gold plating.” The single-row specification uses the same sentence, and the BMI (blind-mate interface) specification narrows it to “20 to 30 AWG wire using crimp technology with tin plating.”

Three structural features do most of the work.

The family is deliberately split into single-row and dual-row, with separate documents for each. Molex maintains PS-43045 for the dual-row system (21 sheets, revision P4 dated 2021/06/03) and PS-43650 for the single-row system (20 sheets, revision N2 dated 2020/08/10). The circuit ranges are different, the mechanical requirements are different, and the header series numbers are different. Anyone cross-referencing this family from a single datasheet page will get the wrong column.

It carries a real locking architecture, not just friction. The housings have a positive latch, and on top of that Molex publishes an optional TPA system — a retainer that locks the crimp terminals in place. That system is a set of real part numbers with its own circuit ranges and its own reduced contact-wipe figures, and it is the reason the final section of this guide asks a specific question about it.

And it reaches well past a single discrete-wire harness. Molex documents compliant-pin (press-fit) headers, surface-mount headers, through-hole headers with kinked or long tails, an FMLB hot-mating terminal that sequences ground before power, a reduced mating force (RMF) terminal, a whole blind-mate floating system that tolerates up to 2.54mm of misalignment, and potting-capable versions that Molex says “do not require the use of sealants.” This is a platform, and that is why the numbers below need careful reading.

The component set, in original part numbers

Part	Molex series	Published range and notes
Female crimp terminal	43030	18–30 AWG; 0.25µm select tin, 0.38µm and 0.76µm select gold
Female crimp terminal, reduced mating force	46235, 203951	46235 is 20–30 AWG with or without lubricant; 203951 is the 18 AWG RMF version
Male crimp terminal	43031	18–30 AWG; 43031-5*** is the TPA plug version, 20–30 AWG; 43031-1*** is the FMLB version
Dual-row receptacle housing	43025	2 to 24 circuits; mates with 43020, 43045, 44914, 44242
Dual-row plug housing	43020	2 to 24 circuits; with or without panel-mount ears
Single-row receptacle housing	43645	2 to 12 circuits; mates with 43640, 43650
Single-row plug housing	43640	2 to 12 circuits; panel-mount and non-panel-mount
Dual-row header	43045, 44067, 44914	2 to 24 circuits; right-angle and vertical; SMT, through-hole kinked pin, through-hole; 44914 is the compliant-pin version, 4 to 24 circuits
Single-row header	43650	2 to 12 circuits; right-angle and vertical; the same three termination interfaces
TPA receptacle / plug / retainer	171850, 172952, 200875, 203632, 172953	171850 and 200875 are single-row, 2 to 7 circuits; 172952 is dual-row, 4 to 22 circuits; 172953 is the retainer, and two TPA parts are required per receptacle
BMI floating system	44133, 44300, 44428, 44432, 44764, 44769, 45280	Dual row, 4 to 24 circuits, 2.54mm misalignment allowance
BMI single-row set	46622, 46623, 46625	2 to 7 circuits
Test plug	44242	Recommended for continuity testing only; 2.5A maximum pogo-pin rating
Off-the-shelf cable assemblies	45132	4 to 8 circuits, 1.0m / 150mm / 300mm

Every one of those series numbers is a real Molex series carrying the Micro-Fit 3.0 interface, and that is worth stating because in an earlier cross-reference in this series the headline finding was that the quoted original part numbers did not exist in the original’s catalogue at all. Here the mapping is sound, and the gaps are gaps in coverage rather than errors in identification — with one exception on our own side that is reported in the defects section below.

The two sub-families we do not publish at all

Two rows of that table have no counterpart in our own catalogue, and both matter to a designer rather than to a buyer.

The TPA system. Molex’s 172952 TPA dual-row receptacle “requires 2 TPA parts for each receptacle” and is available in UL 94V-0, 94V-2, glow-wire and low-halogen versions across 4 to 22 circuits. The single-row TPA parts stop at 7 circuits — a narrower range than the standard single-row housing, which runs to 12. The TPA also changes the electrical geometry: Molex’s own contact-wipe table shows the standard dual-row receptacle wiping 2.11mm when mated to a plug and 1.75mm to a header, while the TPA receptacle wipes 1.72mm and 1.60mm respectively. A shorter wipe for the same interface, published deliberately.

The blind-mate floating system. Molex’s BMI specification is a separate 12-sheet document, and it allows “up to 2.54mm misalignment” between the panel-mounted receptacle and the PCB header, with a published mating-velocity limit: “Molex recommends mating speeds do not exceed 40 mm/sec (1.6 inch/sec) for proper mating.” Our wire-to-board product page describes the series as “still suitable for blind mating applications.” We publish no misalignment allowance, no panel-mount floating receptacle and no mating-velocity limit. That sentence on our page is picked up again in the defects section, because describing a connector as suitable for blind mating without publishing an allowable misalignment is a claim a mechanical engineer cannot design to.

KONNRA KR3000 series single row male housing for the Molex Micro-Fit 3.0 pattern

The Ratings Side by Side

This is the most useful table in the guide, because both manufacturers publish at more than one level — Molex in a family datasheet, in per-system product specifications and in a test summary; KONNRA in a product specification, on product pages and on component pages — and the levels do not always agree with each other.

Figure	Molex family datasheet	Molex product specification	KONNRA spec §4.0	KONNRA product page
Pitch	3.00mm	3.00mm	3.00mm	3.00mm (wire-to-wire page shows 2.0mm in its at-a-glance table)
Rated voltage	600V maximum	600V agency rating (UL, CSA and IEC)	250V	250V
Rated current	Up to 10.5A	5A, 7A or 8A single circuit, depending on the series and the agency	5A (20AWG)	5A
Contact resistance	10 milliohms	10mΩ maximum, initial	10mΩ maximum	10mΩ (product landing page shows 20mΩ)
Insulation resistance	1,000MΩ minimum	1,000MΩ minimum at 500VDC	1,000MΩ minimum at 500VDC	1,000MΩ (product landing page shows 100MΩ)
Dielectric withstanding voltage	Leakage <5mA	two times the rated voltage plus 1,000 volts, VAC, 1 minute	1,500V AC, 1 minute	1,500V (product landing page shows 500V)
Operating temperature	Gold glow-wire −40 to +125°C; tin −40 to +105°C	−40°C minimum; maximum 125°C gold / 105°C tin, by housing type	−40 to +105°C	−40 to +105°C, except two component pages
Applicable wire	18–30 AWG	18–30 AWG (BMI: 20–30 AWG)	20# to 24#	20# to 24#
Insulation diameter	—	1.85mm max (18–24 AWG); 1.27mm max (26–30 AWG)	1.3 to 1.8mm	1.3 to 1.8mm (landing page shows 0.4 to 0.8mm)
Durability	Typically 30 cycles	30 mating cycles, tin or gold	30 cycles	30 cycles
Mating force	8N maximum per circuit	Per circuit, see the mechanical section	0.80kgf per circuit maximum	not published
Unmating force	2.4N minimum per circuit	Per circuit, see the mechanical section	0.25kgf per circuit minimum	not published
Contact insertion force	14.7N maximum per contact	14.7N maximum	1.5kgf (14.7N) maximum	not published
Contact retention to housing	24.5N minimum	24.5N minimum	2.5kgf (24.5N) minimum	not published
Safety agency	UL E29179 · CSA LR19980	UL E29179 · CSA LR19980 · IEC 61984	UL E482542	UL E482542
Housing material	Nylon	See the sales drawing	PA66 UL94 V-0 or V-2	PA66, PA9T, PA46 or LCP
Header material	LCP	See the sales drawing	LCP (SMT) or PA9T / PA46 / LCP (DIP)	Nylon 9T, PA46 or LCP
Contact material	Phosphor bronze, copper alloy	See the sales drawing	Phosphor bronze terminals; brass wafer pins	Phosphor bronze, brass
Plating	0.25µm select tin; 0.38µm and 0.76µm select gold	Tin or gold, thickness by part number	Tin or gold over nickel, thickness not published	Tin over nickel; gold flash

Read the “KONNRA product page” column against the “KONNRA spec” column, because four of the rows do not agree — and in the case of the wire-to-wire pitch, the page contradicts itself. Those are the subject of the second-to-last section.

Three Force Pairs, and Two of Them Are the Original’s Own Numbers

This is the finding of this round, and it is worth setting out slowly because force figures are the easiest thing in a connector datasheet to compare badly. Four separate force measurements exist in these documents and they do not share a basis: per contact, per circuit, whole-connector, and measured-on-a-gage-pin.

Force	Molex published	KONNRA published	Basis	Verdict
Contact insertion force	14.7N maximum per contact	1.5kgf = 14.7N maximum	One contact, into the housing	Identical
Contact retention to housing	24.5N minimum	2.5kgf = 24.5N minimum	One contact, pull-out from the housing	Identical
Mating force	8N maximum per circuit	0.80kgf = 7.85N per circuit maximum	Whole connector, divided by circuits	Ours is 0.15N tighter
Unmating force	2.4N minimum per circuit	0.25kgf = 2.45N per circuit minimum	Whole connector, divided by circuits	Ours is 0.05N stronger
Pin retention in header	13.3N minimum (BMI spec), 13.7N minimum (dual-row spec)	1.5kgf = 14.7N minimum	One header pin, axial push-out	Ours is 1.0–1.4N stronger
Wire pull-out / crimp strength	20 AWG 57.9N, 22 AWG 35.5N, 24 AWG 26.6N minimum (BMI spec); 20 AWG 57.8N, 22 AWG 35.6N, 24 AWG 22.2N minimum (test summary)	6.8 / 4.54 / 3.63kgf minimum = 66.7 / 44.5 / 35.6N at 20 / 22 / 24 AWG	Crimped wire, axial pull	Ours is higher at all three gauges

The first two rows are the strongest claim in this guide, and they are checkable in one arithmetic step. Our specification writes the figures as 1.5 kgf (14.7 N) and 2.5 kgf (24.5 N) — and 1.5 × 9.80665 = 14.710N, 2.5 × 9.80665 = 24.517N. Our documents state both units, the conversion is exact, and the newton figures are the original’s newton figures. These are not two engineers arriving independently at a similar number; they are the same number.

The third and fourth rows are where it gets interesting, because the original’s two figures are a window and our two figures sit inside it. Molex publishes a maximum insertion force and a minimum withdrawal force — a corridor. Converting the corridor to kilogram-force gives 0.8158kgf maximum and 0.2447kgf minimum per circuit. We publish 0.80kgf maximum and 0.25kgf minimum per circuit. The published grid is two decimal places, and both conversions land on the stricter side of the grid: our maximum is lower than the original’s by 0.0158kgf, and our minimum is higher by 0.0053kgf.

I cannot prove from the documents why the table was built that way, and I am not going to claim I can. What I can say is that the arithmetic is reproducible, that the direction is safe in both cases, and that this is the only comparison in this series where a two-sided window on one side is bracketed on both sides by the other. For a designer the practical meaning is simple: the connector we ship is specified to take less force to mate and to hold on harder than the original requires.

Reading the same table as a whole connector

Our §8.0 is more detailed than anything the original publishes, because it is a ladder rather than two numbers — and that makes it worth reconciling against Molex’s per-circuit corridor at the extremes of each range.

Configuration	KONNRA insertion force, max.	Molex at 8N per circuit	KONNRA withdrawal force, min.	Molex at 2.4N per circuit
Single row, 2 circuits	1.60kgf = 15.7N	16.0N	0.50kgf = 4.9N	4.8N
Single row, 6 circuits	4.80kgf = 47.1N	48.0N	1.50kgf = 14.7N	14.4N
Single row, 12 circuits	9.60kgf = 94.1N	96.0N	3.00kgf = 29.4N	28.8N
Dual row, 2 × 6 = 12 positions	9.60kgf = 94.1N	96.0N	3.00kgf = 29.4N	28.8N
Dual row, 2 × 12 = 24 positions	19.20kgf = 188.3N	192.0N	6.00kgf = 58.8N	57.6N

Both columns bracket the original at every circuit count, not just on average. Our maximum insertion force is below the original’s at all five rows and our minimum withdrawal force is above it at all five. And our §8.0 goes further than the original’s mechanical table: it publishes the withdrawal minimum both at initial mate and at the 30th cycle, which the original does not do.

One thing the ladder does not show

Our withdrawal minimum is identical at initial and at the 30th cycle — 0.25kgf per circuit in both columns. That is worth flagging plainly rather than presenting as a strength, because it means the table models no withdrawal-force loss across the full rated life, while our own §7.1 durability clause requires the contact resistance to stay at or below 20mΩ after the same 30 cycles. The original does not publish a force-versus-cycle table at all, so there is nothing to compare against — but a reader should not read “0.25kgf at cycle 30” as a measured value. If retention over life matters to your application, ask us for the measured ladder rather than the specified one.

And the crimp strength, read the right way round

At 20, 22 and 24 AWG our minimum crimp strength is 66.7N, 44.5N and 35.6N against the original’s 57.9N, 35.5N and 26.6N in the BMI specification. The striking line is the third one: our guaranteed crimp strength at 24 AWG, 35.6N, is numerically the same as the original’s guaranteed minimum at 22 AWG, 35.5N. We promise at the finer gauge what the original promises at the coarser one.

Two caveats belong on that paragraph, and they are not small. First, the original publishes two different minimums for 24 AWG — the BMI specification says 26.6N and the test summary requirement column says 22.2N — so the comparison above uses the more demanding of the two. Second, our method is stated as “Crimp strength” with no test rate or standard cited, while Molex specifies the wire pull-out at “25 ± 6 mm (1 ± ¼ inch) per minute.” The figures are comparable in kind but not proven comparable in method. If you are qualifying a crimp, request both test reports rather than the two numbers.

KONNRA KR3000 series female crimp terminal for the Molex Micro-Fit 3.0 pattern

The Electrical Sheet: Five Exact Matches and Three Departures

The five matches are worth listing before the three departures, because a comparison guide that leads with the failures is not useful to an engineer who simply wants to know whether the parts are equivalent.

Item	Molex requirement	KONNRA requirement	Verdict
Contact resistance, initial	10mΩ maximum (20mV, 100mA, dry circuit, wire resistance excluded)	10mΩ maximum (20mV, 100mA, EIA-364-23C)	Match
Insulation resistance	1,000MΩ minimum at 500VDC	1,000MΩ minimum at 500VDC, adjacent contacts, 1 minute	Match, including the test voltage
Durability	30 mating cycles, tin or gold	30 cycles at 10 cycles per minute	Match
Humidity	96 hours at 40 ± 2°C, 90–95% R.H.	96 hours at 40 ± 2°C, 90–95% R.H.	Match
Temperature-rise basis	Derating table based on “not exceeding 30°C temperature rise”	Temperature rise 30°C maximum	Match

The insulation-resistance row is the one to look at twice, because matching the value is easy and matching the test voltage is not. Both documents specify 500VDC applied for one minute between adjacent contacts, and both specify 1,000MΩ minimum. A supplier can pass a 1,000MΩ specification at a lower test voltage and the number looks the same on a datasheet; here it does not.

Now the three departures.

Item	Molex	KONNRA	Direction
Voltage rating	600V, UL, CSA and IEC agency rating	250V	Original is 350V higher
Insulation resistance after humidity	1,000MΩ minimum	100MΩ minimum	Ours is one order of magnitude lower
Salt spray	48 hours at 35 ± 2°C, 5% solution	24 hours at 35 ± 2°C, 5 ± 1% solution	Ours is half the duration

The voltage row is the single most consequential difference in this guide and it deserves to be stated without softening. Molex’s agency rating for the family is 600V — 600V across UL, CSA and IEC for the dual-row and single-row housings and headers — and the family datasheet also quotes 600V maximum at the product level. We publish 250V. A harness that is fine on a 400V DC bus with the original is not covered by our published rating, whatever else matches. This is also the reason our dielectric test level is 1,500V rather than the 2,200V the original’s own formula would demand at 600V, which is discussed immediately below.

On the dielectric withstanding voltage, the original publishes a formula rather than a number, and that is unusually helpful. Molex’s requirement reads: apply “{two times the rated voltage plus 1000 volts} VAC for 1 minute between adjacent terminals and between terminals to ground.” Evaluated at Molex’s own 600V rating that calls for 2,200VAC. Our §5.3 states 1,500V AC for 1 minute — which is precisely what the same formula yields at 250V (2 × 250 + 1,000 = 1,500). Our withstand test level is therefore not arbitrary; it is the original’s own formula evaluated at our published rating. The test level is consistent with our rating, and the gap between the two companies on this row is the voltage rating, not the test method.

The post-humidity insulation resistance is the row where we are weakest, and it is worth naming a pattern: our §7.7 requires 100MΩ minimum after humidity while the original requires 1,000MΩ — an order of magnitude. The same clause value appears in our 2.5mm, 2.54mm and 3.00mm specifications, so this reads as a family-template figure rather than a tested result for this series. If your application sits in condensing or high-humidity duty, this is the row to raise at enquiry.

Why the original’s own test report reads 19.95mΩ against a 10mΩ limit

One measurement-basis trap in these documents is worth knowing about before you compare anything.

Molex’s test summary TS-43045-001 reports an initial contact resistance mean of 19.95mΩ — minimum 19.74mΩ, maximum 20.40mΩ — against a requirement of 10 milliohms maximum. Read alone that looks like a failure. The note underneath explains it: “APPROXIMATELY 16.6mW OF THE MEASUREMENT VALUE IS ATTRIBUTED TO THE BULK RESISTANCE OF THE 13 INCHES OF WIRE USED IN SAMPLE PREPARATION.” Stripping the wire out leaves roughly 3.4mΩ of actual contact resistance. The same document reports the wire-to-board configuration, prepared with a shorter wire, at 4.75mΩ initial — comfortably inside the limit.

The equivalent trap on our side is the wording of §5.1, which specifies the dry-circuit measurement at 20mV and 100mA “between adjacent contacts” on the mated connector. Neither number is comparable to a fixture measurement or to a harness-level reading. When two suppliers quote 10mΩ and 10mΩ, as here, that agreement is only meaningful if the measurement basis is the same — and in this family it is.

The Wire Window: Three of the Original’s Seven Rated Sizes

Molex accepts 18 to 30 AWG stranded copper wire. We document 20# to 24#.

AWG	Molex derating table, 2-circuit W-B	Molex derating table, 24-circuit W-B	KONNRA coverage
18 AWG	8.5A	5.0A	not covered
20 AWG	7.0A	4.5A	covered
22 AWG	6.0A	3.5A	covered
24 AWG	5.5A	3.0A	covered
26 AWG	4.5A	2.5A	not covered
28 AWG	4.0A	2.0A	not covered
30 AWG	3.5A	1.0A	not covered

Five nominal AWG steps out of thirteen, and three rows out of seven in the original’s own table. Four of the misses are fine gauges we simply do not document, which is a coverage statement rather than a defect for most power applications. The one that matters commercially is 18 AWG, because that is where the original’s headroom lives: 8.5A in a 2-circuit wire-to-board configuration, against our published 5A at 20 AWG. A customer using 18 AWG for a 6A load on a two-way connector is outside our documented window, and per Molex’s own reference table the original covers it. That single row is the strongest technical argument for staying on the original — and it is the first thing to check before quoting a cross-reference.

Read the table with the original’s own caveat attached, because Molex prints it prominently: the values are “for REFERENCE ONLY”, they are based on “not exceeding 30°C Temperature Rise”, the data is “for all circuits powered”, and “PCB trace design can greatly affect temperature rise results in Wire-to-Board applications.” Molex also states plainly that “Current rating is application dependent” and that “each application should be evaluated by the end user.” Our single 5A figure is a rating, not a derating table, and the two are not the same kind of number.

On current, one comparison is genuinely favourable and worth stating precisely. Molex’s test summary measures 20 AWG at 5.5A and 24 AWG at 4.0A at 30°C maximum temperature rise. Our published rating is 5A at 20 AWG. So at the coarsest gauge in our documented window we are rating the part slightly below what the original measured for the same conductor — a conservative publication, not an optimistic one. The original’s headline family figure of up to 10.5A and its single-circuit agency ratings of 8A on the receptacles and headers / 5A on the plugs sit above both, so the honest summary is that we under-publish at the gauges we cover and do not cover the gauges where the original goes highest.

And the insulation window is narrower at both ends

	Molex	KONNRA
18–24 AWG	1.85mm maximum	—
26–30 AWG	1.27mm maximum	—
20–24 AWG	1.85mm maximum	1.3 to 1.8mm

The original publishes a ceiling. We publish a corridor. That is not the same shape of requirement, and both of our ends exclude wires the original accepts.

• At the top end we are 0.05mm tighter. A 24 AWG wire with 1.83mm insulation is inside the original’s published maximum and outside ours.
• At the bottom end we impose a floor the original does not impose at all. A thin-wall 22 AWG wire with 1.2mm insulation is covered by the original’s document and rejected by ours.

A 0.05mm difference at the top is small enough to be invisible at the quotation stage and large enough to stop a crimp from closing, which is exactly the failure mode this series of guides keeps finding. The floor is the bigger risk: no Molex Micro-Fit document states a minimum insulation diameter, so a designer who has validated one with thin-wall wire has no reason to look for a lower bound — and our window would reject it. If your wire is a thin-wall or a dual-wall type, send the insulation diameter before you specify.

KONNRA KR3000 series DIP dual row straight wafer, vertical 3.00mm header

Materials: Nylon and LCP on One Side, Three Resins and a V-2 Grade on the Other

Molex’s family datasheet states the physical set in four lines: “Housing: Nylon. Header: LCP. Contact: Various (Phosphor Bronze, Copper Alloy — see product specifications for exact connector system).” The plating options are published to the micron: 0.25µm select tin, or 0.38µm and 0.76µm select gold.

Our set is more granular and less consolidated. From our specification §3.0 and the engineering drawings:

Component	Molex	KONNRA
Male housing	Nylon	PA66, UL94 V-0 or V-2
Wire-to-wire female housing	Nylon	Nylon66, UL94 V-2
SMT wafer base	LCP	LCP, UL94 V-0
DIP wafer base	LCP	PA9T, PA46 or LCP, all UL94 V-0
Terminal	Phosphor bronze / copper alloy	Phosphor bronze
Wafer contact pin	Phosphor bronze / copper alloy	Brass, matte tin or tin/gold over nickel
Plating thickness	0.25µm tin; 0.38µm / 0.76µm gold	not published

Three points follow from that table.

Our DIP wafers are documented in three different resins across different part numbers. Our specification lists the DIP base as “PA9T or PA46 or LCP UL94 V-0”, and the component pages resolve to the individual part: the DIP single-row right-angle wafer page publishes Nylon 9T (PA9T), the DIP dual-row straight wafer page publishes PA46, and the SMT dual-row right-angle wafer page publishes LCP. The original’s header material is one answer — LCP — and ours is three answers by part number. That is not a defect in the products, but it is a documentary burden: a designer comparing reflow behaviour has to check the specific wafer code rather than the series. If you are matching a reflow profile, ask for the resin on the exact part number you intend to buy.

One housing grade on our side is UL94 V-2, not V-0. The male housing is available in either grade as a documented ordering option, but the wire-to-wire double-row female housing is published as Nylon66 UL94 V-2 on our own engineering drawing, and its part-number suffix carries the same V-2 material code. Molex’s standard Micro-Fit housings are UL 94V-0, with 94V-2 available only as an option on the TPA dual-row receptacle 172952. So we can match V-0 across most of the range and do not match it on that one housing. In a flame-retardancy-governed application, check the grade on the specific housing, not the series.

And we publish no plating thickness anywhere. Molex’s 0.25µm tin and 0.38µm/0.76µm gold call-outs are what a durability calculation is built on — thicker gold is how the original reaches 1,000 hours of thermal ageing at 125°C with gold-plated terminals, against 240 hours at 105°C with tin. Our specification says “Tin/Gold Plated Over Nickel” and stops. For an application where mating cycles or corrosive atmosphere matter, that is a specification gap and not a product gap — but it has to be closed in writing before qualification, which is why it appears again in the questions at the end.

Where our specification does something better than the original deserves saying too. Our wire-to-wire specification marks the entire wafer block N/A — §2.0 lists the wafer as “None”, and §3.0 records “N/A” for the SMT base, contact and solder tab, and again for DIP. A wire-to-wire connector has no header, so the correct value in those rows is not a blank, it is an explicit non-applicability — and our document says so. Our wire-to-wire specification also carries no solderability or solder-resistance clause, which is right for a part that is never soldered. That is a document doing the correct thing with a section that does not apply.

KONNRA KR3000 series SMT single row right angle wafer with solder tab, 3.00mm reflow header

Environmental and Process: Where the Test Methods Diverge, Not Just the Durations

Duration comparisons are easy and mostly unhelpful on their own. The more important finding in this layer is that two clauses cite the same standards but test different things.

Test	Molex	KONNRA	Reading
Heat resistance	240 hours at 105°C (tin, dual row); 1,000 hours at 125°C (gold)	96 hours at 105°C	Ours is 2.5× shorter against the standard family; equal to Molex’s own BMI variant, which also specifies 96 hours at 105°C
Cold resistance	96 hours at −40°C	96 hours at −40°C	Match
Thermal shock	5 cycles −40/+105°C (BMI dual row); −55/+85°C in the standard test sequence	5 cycles: −40°C 30 min / room 5 min / +105°C 30 min / room 5 min	Match with the BMI variant; the standard family’s thermal-shock sequence is a wider −55/+85°C
Humidity	96 hours at 40°C, 90–95% R.H.	96 hours at 40°C, 90–95% R.H.	Match; Molex’s BMI variant uses 85°C instead
Vibration	Random vibration, EIA-364-28 test condition VII	EIA-364-28B, amplitude 1.5mm peak-to-peak, 10→55→10 Hz swept in 1 minute, 2 hours in each of X, Y and Z	Same standard number, different excitation
Shock	50 g, half-sine, 11 ms duration, 18 shocks total (±X, ±Y, ±Z)	490 m/s² (50 g), 3 strokes in each axis (9 total)	Same acceleration, no pulse duration or waveform published on our side
Salt spray	48 hours	24 hours	Ours is half the duration
Thermal cycling / fretting	500 cycles between 15 and 85°C, contact resistance allowed to change by 20mΩ	Not published	Original only
Corrosive atmosphere	Flowing mixed gas, EIA-364-65 class 2A, 10 days unmated then 10 days mated (gold-with-lubricant terminals only)	Not published	Original only
Capacitance	2 picofarads maximum between adjacent terminals at 1 MHz (BMI spec)	Not published	Original only
Normal force	2.7N (0.6 lbf) minimum, measured at 331g mean in the test summary	Not published	Original only

The vibration row is the one to slow down on. Both documents cite EIA-364-28, and a comparison table that stops there would call it a match. It is not one. Molex specifies random vibration at test condition VII. Our clause specifies a sinusoidal sweep — 1.5mm peak-to-peak, 10 to 55 to 10 Hz in one minute, two hours per axis. These are different excitations producing different damage mechanisms, and a sine-sweep pass does not predict a random-vibration pass. If your application has a vibration qualification, send the profile and ask us to test to it rather than assuming the standard number transfers.

The shock row has the same shape of problem in a milder form. Both sides use 50 g. Molex specifies the pulse shape and duration — half-sine, 11 milliseconds — and applies 18 shocks. Our clause gives the acceleration, the axis count and the stroke count, and publishes no waveform or duration. A shock requirement without a pulse duration is not fully specified, and that is a fair thing for a customer to push back on.

The solder profiles run cooler on our side and carry fewer parameters

Parameter	Molex (reflow)	KONNRA (SMT, §9.1)	Molex (wave)	KONNRA (wave, §9.2)
Peak temperature	260 +0/−5°C	255 ± 5°C	260°C maximum	250°C maximum
Time at peak	20 to 40 sec within 5°C of peak	5 to 10 sec	10 sec maximum dip	3 to 5 sec
Preheat	150–200°C, 60 to 180 sec	150–200°C, 90 to 120 sec	—	150–180°C, 60 to 180 sec
Time above liquidus	60 to 150 sec above 217°C	20 to 40 sec above 230°C	60 to 150 sec above 217°C	60 to 150 sec above 217°C
Ramp rate	3°C/sec maximum, 6°C/sec cooldown	not published	—	not published
Time from 25°C to peak	8 minutes maximum	not published	—	not published

Our SMT peak is 5°C below the original’s and our wave peak is 10°C below it, which is the safe direction — a lower peak is easier to keep inside, not harder. The gap is in the parameters we do not publish: no ramp rate, no time-to-peak, and a different anchor for the “time at temperature” row (we measure above 230°C, the original measures within 5°C of peak). If you are matching this part into an existing profile that was qualified on the original, the peak is the only row you can line up directly; the rest has to be measured.

Both documents also put the same caveat on the profile, and it is not boilerplate. Ours reads: “Please check welding conditions by your own devices beforehand. Because the condition changes by the soldering devices, P.C.boards, and so on.” Molex’s: “Solder Process Temperatures and Reflow Solder Profiles will vary based on application, equipment, solder paste, PCB thickness, etc.”

What the Original Publishes That We Do Not

A cross-reference guide that lists only what the two parts share is a sales document. This section is the engineering one. Every item below is something a Molex document states and ours does not, and the correct response to each is a document request rather than an assertion.

Plating thickness. Molex publishes 0.25µm select tin and 0.38µm / 0.76µm select gold over nickel. We publish “Tin/Gold Plated Over Nickel” and no thickness. This is the input to a durability or corrosion calculation.

Agency coverage. Molex carries UL file E29179 and CSA file LR19980, and states that the family is “Tested to and found in compliance with IEC 61984” with an “NRTL type examination certificate available from Molex upon request.” Our component pages publish UL E482542 only. A customer whose file already references a CSA registration has a gap to close with us even though the UL file exists.

Contact wipe. Molex publishes the nominal wipe for every mating combination: 2.11mm for the dual-row receptacle to plug, 1.75mm receptacle to header, 1.72mm and 1.60mm for the TPA versions, with equivalent figures for the single-row set. We publish no wipe figure at all. Wipe interacts with fretting corrosion and with contact resistance over life, so a low-current or dry-circuit application should ask for it.

Capacitance. Molex’s BMI specification limits capacitance to 2 picofarads maximum between adjacent terminals at 1 MHz. We publish none. For a signal or a switching node sharing the connector, this is a specification the original has and we do not.

Normal force. Molex requires 2.7N (0.6 lbf) minimum and its test summary reports a measured mean of 331g with a minimum of 322g. We publish none.

Panel-mount and latch figures. Molex publishes panel-mount retention at 155.7N minimum for the dual-row set, 89.0N for the single-row plug and 111.2N for the TPA single-row plug, plus thumb-latch-to-ramp yield strength of 58.0N wire-to-board and 45.0N wire-to-wire for the dual row and 68.4N for the single row. None of these appear in our documents, and they are exactly the numbers a harsh-environment or appliance customer asks for first.

Compliant-pin (press-fit) data. Molex publishes 106.7N maximum insertion force per terminal and retention of 35.6N on a tin-plated plated-through hole or 13.3N on an OSP finish. We publish no press-fit product.

The free-length rule for wire dress. Molex defines a minimum “T” dimension — 12.70mm for 2 to 8 circuits, 19.10mm for 10 to 16, 25.40mm for 18 to 24 — beyond which “wires are to be dressed in such a manner to allow the terminals to float freely in the pocket” when a cable tie or wire twist is used. We publish no equivalent guidance, and it is the kind of application note that prevents a field failure.

The test-plug recommendation. Molex recommends using test plug 44242 for continuity testing of receptacles and warns that “standard mating parts should not be used for harness testing.” We publish no equivalent. A harness shop using production mating halves as test probes wears out the very parts it ships.

Halogen-free and glow-wire status. Molex’s datasheet states “Halogen Free: Yes (non-Glow-Wire versions)” and lists “Halogen-free, V0 and Glow Wire capable” under industry standards, with glow-wire compliance to EN 60695-2-11 / IEC 60695-2-11 and testing to IEC 60335-1 750°C / 2 seconds with no flaming, VDE report available on request. We publish no halogen-free declaration and no glow-wire data for this series.

The FMLB and RMF terminal options. Molex offers a hot-mating FMLB terminal (43031-1***) that sequences ground before power, and a reduced-mating-force terminal (46235, 203951) with or without lubricant. Our series publishes two female terminals — T3000FP***01A and T3000FP***01C — and does not state what distinguishes them, which is itself a question worth asking before you assume one of them plays the RMF role.

Where Our Own Documents Disagree With Each Other

This section exists because a cross-reference is only as good as the weaker of the two catalogues, and ours has internal contradictions in this family that a careful buyer will find. All of these are reported rather than smoothed over.

1. The wire-to-board landing page publishes four electrical values that belong to a different product.

Field	Landing page publishes	Our own specification says	Two sibling pages say
Insulation O.D	0.4 to 0.8mm	1.3 to 1.8mm	1.30–1.80mm
Withstanding voltage	500V AC / minute	1,500V AC 1 minute	1,500V AC
Contact resistance	20mΩ max	10mΩ max	10mΩ max
Insulation resistance	100MΩ min	1,000MΩ min	1,000MΩ min

All four values also appear on the other two KR3000 product pages with the correct figures, so this is a single page disagreeing with the rest of its own family. The insulation row is the one to treat as urgent, because 0.4 to 0.8mm is narrower than a real 20–24 AWG wire’s insulation — the field is wrong in the direction that would cause a designer to reject a wire that actually fits. This is also the third time this field has been found holding a foreign value in this series of reviews, which suggests the field is being populated from a template rather than from the specification.

2. The wire-to-wire product page states a 2.0mm pitch in its specification block. The page title, every image filename and the body text of the same page say 3.00mm. Pitch is the first thing a cross-reference is checked on, and a 2.0mm pitch on a Micro-Fit page points a buyer at an entirely different family.

3. The same wire-to-wire page contradicts itself on temperature. Its blurb states the family “can withstand operating temperatures up to 125°C”, while the specification table immediately below it — and our own specification §4.0 — says −40 to +105°C. The 125°C figure is the original’s gold-plated ceiling, not ours; we publish 105°C as the maximum for the whole series, so the page is quoting the competitor’s number against our own table.

4. Two component pages still carry the −25°C to +85°C temperature range. The male terminal page and the single-row female housing with wings page publish −25℃~85℃, while the other component pages in the same family and both product specifications publish −40 to +105°C. Fifty-six component pages across this catalogue use one or the other, and in this family the two pages are simply on the wrong one.

5. The male terminal component page publishes a wire range and an insulation diameter that no other document in the family supports. It states AWG 28#–22# and insulation 1.80mm (Max), against our specification’s 20# to 24# and 1.3 to 1.8mm. The female terminal page next to it publishes the correct 20#–24# and 1.30–1.80mm. Two terminals in the same series, two different wire windows on the website, one window in the specification.

6. The “Compatible” field is used with two different meanings inside one family, and one of the two must therefore be wrong. This is the subtlest item in this section and the most likely to cause a wrong order.

Page	Part on the page	Field reads	If “Compatible” means replaces	If it means mates with
Female terminal	female crimp terminal	43030 or 46235-0001	correct	wrong (a female terminal does not mate with a female terminal)
Male terminal	male crimp terminal	43031-0001	correct	wrong
DIP single-row right-angle wafer	header	43650	correct	wrong (a header does not mate with a header)
Single male housing	plug housing	43645	wrong — 43645 is the receptacle; the single-row plug is 43640	correct
Single-row female housing, with wings	receptacle housing	43640	wrong — 43640 is the plug; the single-row receptacle is 43645	correct
Dual-row male housing	plug housing	43025	wrong — 43025 is the receptacle; the dual-row plug is 43020	correct

The terminals and wafers only make sense under “replaces”; the three housings only make sense under “mates with”. They cannot both be right. Under the reading that the rest of the family uses, the three housing pages should read 43640, 43645 and 43020 respectively — the same gender as the part on the page. Until the field label says which meaning it carries, a buyer quoting “our 43645 equivalent” off the male housing page is ordering the wrong half of the pair. The two gender names are the trap: in Molex’s own naming, the receptacle holds the female crimp terminals and the plug holds the male crimp terminals.

7. Our wire-to-board specification’s crimp table is titled “(Male Terminal)” while its own part list contains no male terminal. Section §6.5 of PS-KR3000-01 is headed “Terminal Crimping Specification (Male Terminal)” and gives the crimp dimensions and strength for 20, 22 and 24 AWG — but §2.0 of the same document lists the terminals as T3000FP***01A and T3000FP***01C, both of which are female. In the wire-to-wire specification the same table is headed male and the part list does include the male terminal T3000MP***01B, so the heading is right there and unverifiable here. Either the wire-to-board document is missing a male terminal from its part list, or the heading is a template leftover. Both are worth fixing before a customer asks which terminal the crimp table belongs to.

1. The engineering drawings and the product specification describe different female housings. Our wire-to-wire specification §2.0 lists four female housings — H3000F1**0401B, H3000F1**0402B, H3000F2**0401B, H3000F2**0402B — while the drawing set shows a double-row female housing part number of the form H3000F*****02B with the material stated as Nylon66 UL94 V-2. The suffix positions carry the material code (the male housing’s ordering code decodes 02 as PA66 UL94 V-0 and 04 as PA66 UL94 V-2), so the four listed housings are the V-2 grade. That is consistent once decoded, but it is not decodable from the specification alone, and the V-0/V-2 difference is a qualification item.

9. The KR3000 wiring harness page is empty. It shows a hero image, an enquiry form and the category list, and nothing else: no specification, no engineering drawing, no package specification, and its component selector returns “No results found.” Every other page in this family links a specification, a package specification and a series drawing. A customer searching for a 3.00mm harness lands there.

10. Two smaller items. The component pages are named with two different prefixes for the same series — mx3-0-vd-dual, mx3-0-rs-dual, mx3-0-rd-single-wf alongside kr3000-single-row-m-hsg, kr3000-female-terminal, kr3000-male-terminal — and three slugs carry a trailing full-width bracket, which encodes into the URL as %EF%BC%89. Neither breaks a page; both make the family harder to search and to audit.

11. And one existing page in the same family is out of step with this review. The site already carries an article, “KONNRA KR3000 connector eliminates assembly errors and prevents fallout”, which describes a “high-temperature UL 94V-0 liquid crystal polymer” housing, calls the part “glow wire compatible”, and states a “2 to 24 circuits” range. Our own specification says the housing is PA66 UL94 V-0 or V-2, the drawings say Nylon66 UL94 V-2 on the wire-to-wire female housing, we publish no glow-wire data, and the wire-to-board range is 2 to 12 circuits single row and 2×1 to 2×12 dual row. Separately, a KR3000 landing page on the same site is titled with “Mini-Fit 3.0” — Mini-Fit is Molex’s 4.2mm family, an entirely different pitch. Neither page is part of this guide, and both are worth a review so that the KR3000 story reads consistently across the site.

KONNRA KR3000 series single row female housing for the Molex Micro-Fit 3.0 pattern

The Cross-Reference Map

How to read it: the left column is our part, the middle column is the Molex series it corresponds to, and the right column states what our documents publish. Where a page’s own compatibility field is in question, the series named here is the one that matches the part’s gender and function.

KONNRA component	Molex series	KONNRA part number pattern	Positions
Single-row male housing	43640 (single-row plug)	H3000M1****01A	2 to 12
Dual-row male housing	43020 (dual-row plug)	H3000M2****01A	2×1 to 2×12
Single-row female housing	43645 (single-row receptacle)	H3000F1**04**B	2 to 12
Dual-row female housing	43025 (dual-row receptacle)	H3000F2**04**B	2×1 to 2×12
Female crimp terminal	43030, 46235	T3000FP***01A, T3000FP***01C	—
Male crimp terminal	43031	T3000MP***01B	—
SMT right-angle wafer, single row	43650 (single-row header)	C3000RS1*****	2 to 12
SMT right-angle wafer, dual row	43045 (dual-row header)	C3000RS2*****	2×1 to 2×12
SMT straight wafer, single row	43650	C3000VS1*****	2 to 12
SMT straight wafer, dual row	43045	C3000VS2*****	2×1 to 2×12
DIP right-angle wafer, single row	43650	C3000RD1*****	2 to 12
DIP right-angle wafer, dual row	43045	C3000RD2*****	2×1 to 2×12
DIP straight wafer, single row	43650	C3000VD1*****	2 to 12
DIP straight wafer, dual row	43045	C3000VD2*****	2×1 to 2×12
TPA	171850, 172952, 200875, 203632, 172953	none published	—
Blind-mate floating set	44133, 44300, 44428, 44432, 44764, 44769, 45280	none published	—
Compliant-pin header	44914	none published	—

Every Molex series in that table is a real Micro-Fit 3.0 series, and the four families in the last three rows are the coverage gaps rather than identification errors. The wafer part-number pattern is the one field worth treating carefully: our wafer ordering codes are compound — family, orientation, row count, circuit count, a type code, a variant letter and a plating code — and they cannot be decoded from the product specification alone. The engineering drawings decode them; the website does not. Ask for the drawing and for the exact code rather than assembling one from a page.

One practical note for anyone moving a design across. Our T3000FP***01A and T3000FP***01C are two female terminals for one interface, with no published statement of the difference — and the original’s own catalogue answers the analogous question explicitly, because Molex’s 46235 is documented as the reduced mating force version against the standard 43030. If insertion force is your constraint, that is the question to put to us in writing, because the answer may already exist and simply not be published.

Applications Where the Micro-Fit Pattern Is Used

Molex publishes its own market and application list for this family, and it is a more accurate statement of where the pattern is used than any general claim about “power connectors” could be. From the family datasheet:

Market	Applications as published
Appliance	Freezers, HVAC systems, printers, refrigerators, scanners, security systems, smart homes, washing machines
Automotive	Harness manufacturers, interior automotive devices, non-sealed applications
Industrial	Routers and switches, servers, storage systems
Power for data centre	Routers and switches, servers, storage systems
Telecommunications	Routers and switches, servers, storage systems

Three of the five market rows point at the same three applications, and that is the honest summary of this family’s centre of gravity: board-level power distribution inside equipment that is not sealed and not exposed to the weather. The datasheet is explicit about the automotive limit — “non-sealed applications” — and equally explicit about the appliance set, which is where a UL 94V-0 housing, a positive latch and a 5A rating earn their keep.

What the application list implies for a cross-reference check:

• Appliance and HVAC programmes are usually governed by glow-wire and flame-retardancy requirements, plus a UL file in the customer’s existing approval. That is the first place our missing glow-wire data and missing CSA registration become an active problem rather than a documentation note.
• Data-centre power runs at higher currents than our 5A publishes, and it is where the original’s 18 AWG row at 8.5A and the compliant-pin 44914 header matter. If your load is above 5A per circuit, this cross-reference needs the derating conversation before anything else.
• Automotive interior, non-sealed is where vibration and thermal cycling dominate. Both sides run vibration to a form of EIA-364-28, but as the environmental section showed, ours is a swept sine and the original’s is random at condition VII — so a customer with an existing vibration qualification should send the profile rather than accept the standard number.

Cable assembly options

The original publishes two structured assembly routes plus two custom ones: the off-the-shelf 45132 TPA discrete-wire assemblies in 4 to 8 circuits at 1.0m, 150mm and 300mm, the over-moulded assembly specification 430250000-AS, and, on the custom side, “Customized Micro-Fit Overmolded Cable Assemblies” and “Customized Micro-Fit Discrete Wire Cable Assemblies.” Molex also states the family is potting capable and requires no sealants.

We supply the KR3000 as components, as crimped housing assemblies, and as finished harnesses — the KR3000 wiring harness page exists for that purpose, though as noted above it currently carries no specification or drawing. If your programme needs a harness rather than components, ask for the drawing package at the same time as the quotation, because the harness route is where the assembly-level tests — pull-out, retention, continuity and the free-length rule — actually get exercised.

Sourcing: What Procurement Teams Ask

A cross-reference enquiry fails for commercial reasons far more often than technical ones, and the commercial questions in this family have specific answers.

Which half of the pair am I buying? This is the single most common error with a 3.00mm crimp system, and in our own catalogue the ambiguity is documented above: the male housing and the female housing are different parts with different part numbers, and the “Compatible” field on three of our housing pages currently names the opposite gender. If you are quoting from a page, quote the part number rather than the compatibility field.

Is the wire I already use inside the window? 20# to 24# with 1.3 to 1.8mm insulation. Two exclusions catch people: 18 AWG is outside it, and any wire with insulation below 1.3mm is outside it even though the original sets no such floor.

What is the minimum order quantity and the lead time? Connector production lead time is typically 2 to 4 weeks and wiring harness lead time typically 3 to 4 weeks, with complete connector set samples within 45 days. Samples are the right first step for this family, because the three things most likely to differ from your current part — the wire window, the resin on a specific wafer code, and the plating thickness — are all confirmed faster on a sample than in a drawing.

What documentation arrives with the parts? Ask for the product specification, the package specification and the series drawing, then the component drawing for each part number you are buying. Our family publishes all three at product level, which is stronger than many suppliers; the gap is at component level, where the crimp geometry and the plating thickness are thinner than the original’s.

Can you hold the specification? Your contract should reference the part number and the specification revision — PS-KR3000-01 revision A1 for wire-to-board and PS-KR3000-02 revision A1 for wire-to-wire — and it should say which housing grade and which plating you are buying. Our own specifications carry a Remark section that states plainly: “Any change or revision for the product specification will not be announced in advance.” That sentence is why the revision number belongs in the purchase order.

What about the second source? This is the last section’s subject, and the answer for this family is unusually favourable: the mechanical layer matches the original’s published numbers closely enough that a drop-in evaluation is credible on fit and retention, while the voltage rating and the coarse-gauge current window are the two places a real second source has to be assessed against the actual load.

The Five Questions I Would Ask Us, In This Order

If I were the engineer on the other side of the table, these are the questions I would put to KONNRA before doing anything else — and they are ordered by what is cheapest to answer, not by what is easiest.

1. “My circuit is 400V DC. Is the KR3000 rated for it?” No. Our published rating is 250V; the original’s agency rating is 600V. This is the first question because it can end the conversation in one line, and it should: a 250V rating on a 400V bus is not a documentation gap, it is outside the specification.

2. “I use 18 AWG at 6A on two circuits. Does the KR3000 cover it?” No. Our documented range is 20# to 24#. The original’s own derating table rates 18 AWG at 8.5A in a 2-circuit wire-to-board configuration. This is the second question because it is the same kind of answer as the first — a coverage limit, not a quality difference.

3. “My wire has 1.2mm insulation. Will it crimp?” Not to our published window, which starts at 1.3mm — and the original publishes no lower bound at all, so a designer with thin-wall wire has no reason to expect this constraint. Ask as a diameter, not as a gauge.

1. “What does the second female terminal do that the first one does not?” We publish T3000FP***01A and T3000FP***01C and no statement of the difference, while the original documents its second female terminal explicitly as the reduced mating force version. If insertion force matters in your assembly, this is the highest-value question on the list, because the answer may already exist inside our own engineering files.

5. “What is the retention force after 30 cycles, measured rather than specified?” Our §8.0 table gives 0.25kgf per circuit at both initial and cycle 30, which models no loss over life. The original publishes no equivalent table. Ask for the measured ladder.

Engineer’s Pre-Release Checklist

Nine checks, in the order the failures actually happen.

1. Voltage. Confirm the working voltage against 250V, not against the original’s 600V. Include transients and any DC bus.
2. Current at your gauge. Our rating is 5A at 20 AWG. If you are at 22 or 24 AWG, or above 5A, ask for the derating answer for that combination in writing — the original publishes a table and we publish a point.
3. Wire. Check the gauge (20#–24#) and the insulation diameter (1.3–1.8mm) separately. A wire can pass one and fail the other.
4. Housing grade. Confirm UL94 V-0 on the specific housing. Our wire-to-wire double-row female housing is published as V-2, while the original’s standard Micro-Fit housings are V-0.
5. Wafer resin. Reflow and soldering behaviour depends on the base material, and our DIP wafers appear as PA9T, PA46 or LCP depending on part number, while the original’s header is LCP. Confirm the resin on the exact code you are buying.
6. Solder profile. Our SMT peak is 255 ± 5°C against the original’s 260 +0/−5°C, and we publish no ramp rate and no time-to-peak. If you are re-profiling, measure rather than substitute.
7. Vibration and shock. Our vibration clause is a swept sine to EIA-364-28B while the original specifies random vibration at condition VII; our shock clause gives 50 g and 3 strokes per axis with no pulse duration, against the original’s 11 ms half-sine and 18 shocks. Send your profile.
8. Environmental life. Heat ageing is 96 hours at 105°C against the original’s 240 hours, humidity is 96 hours at 40°C on both sides, and salt spray is 24 hours against the original’s 48. Post-humidity insulation resistance is 100MΩ on our side against 1,000MΩ on the original’s — check this row in any condensing application.
9. Retention. If the connector will be handled after assembly, ask for the measured pull-out ladder rather than the specified one, and confirm the terminal-to-housing minimum of 2.5kgf (24.5N).

Frequently Asked Questions

What is a Molex Micro-Fit 3.0 connector?

It is Molex’s 3.00mm (.118 inch) pitch crimp connector family for wire-to-board and wire-to-wire power and signal connections, built on a positive friction lock with an optional terminal position assurance device. Molex documents it across separate single-row and dual-row product specifications, with female crimp terminals in 43030 and 46235, male crimp terminals in 43031, housings in 43020, 43025, 43640 and 43645, and headers in 43045, 43650, 44067 and 44914. Molex rates the family at 600V and up to 10.5A, from −40 to +105°C with tin plating and −40 to +125°C with gold, over 2 to 24 circuits.

Is Micro-Fit 3.0 the same as MX3.0?

Yes — MX3.0 is the short name for the same 3.00mm pitch system, and it is the name used across our own component pages and product images. When you see “MX3.0” on our site, it refers to the Molex Micro-Fit 3.0 interface and to the KONNRA KR3000 as its cross-reference. The one place the naming matters commercially is that “MX3.0” is not a Molex part number prefix — Molex identifies the family by series number, not by pitch.

Is Micro-Fit the same as Mini-Fit?

No, and the two are routinely confused. Micro-Fit is 3.00mm pitch. Mini-Fit is 4.2mm pitch. They are different families, different terminals, different current ratings and not interchangeable. Our own site has a KR3000 page titled with “Mini-Fit 3.0”, which mixes the two names; if you are searching for the 4.2mm family, it is a different article and a different KONNRA series.

What is the KONNRA equivalent of the Molex Micro-Fit 3.0?

The KR3000 series — a 3.00mm pitch crimp family covering wire-to-board and wire-to-wire, in 2 to 12 circuits single row and 2×1 to 2×12 dual row, with PA66 housings, LCP/PA9T/PA46 wafers, phosphor bronze terminals and brass wafer pins. Our published ratings are 250V, 5A at 20 AWG, −40 to +105°C, 10mΩ contact resistance and 1,000MΩ insulation resistance at 500VDC.

What voltage and current does the Micro-Fit 3.0 carry, and what does the KR3000 carry?

Molex rates the family at 600V, with agency single-circuit current ratings of 8A on the dual-row and single-row receptacles and headers and 5A on the plug housings, plus a headline “up to 10.5A” in the family datasheet. Our published rating is 250V and 5A at 20 AWG. Molex’s own test summary measures 20 AWG at 5.5A and 24 AWG at 4.0A at 30°C maximum temperature rise, so our single published figure is conservative at the gauge it names — but it is a rating, not a derating table, and the two are not interchangeable.

What is the contact resistance and insulation resistance of the Micro-Fit 3.0?

Contact resistance: 10 milliohms maximum, initial, measured at 20mV and 100mA with wire resistance excluded. Insulation resistance: 1,000 megohms minimum, measured at 500VDC for one minute between adjacent contacts. The KR3000 publishes the same two figures with the same test conditions — 10mΩ maximum and 1,000MΩ minimum at 500VDC — which is the closest electrical agreement in this comparison. Note that Molex’s own test summary reports 19.95mΩ for the wire-to-wire configuration, of which roughly 16.6mΩ is the bulk resistance of 13 inches of test wire; the same document reports 4.75mΩ for wire-to-board. Measurement basis matters more than the headline number.

What is the dielectric withstanding voltage?

Molex publishes a formula rather than a figure: two times the rated voltage plus 1,000 volts, applied as VAC for one minute between adjacent terminals and between terminals and ground. At Molex’s own 600V rating that is 2,200VAC. Our specification states 1,500V AC for one minute, which is exactly what the same formula yields at 250V — so our test level is consistent with our published rating, and the difference between the two companies on this row is the voltage rating, not the test method.

What wire gauge does the Micro-Fit 3.0 accept?

18 to 30 AWG stranded copper, with crimp termination and tin or gold plating. Molex’s blind-mate floating variant narrows this to 20 to 30 AWG. The KR3000 documents 20# to 24# — three of the seven conductor sizes in Molex’s own current-derating table. The gap that matters commercially is 18 AWG, which Molex rates at up to 8.5A in a 2-circuit wire-to-board configuration and which our window does not include.

What insulation diameter does it accept?

Molex publishes a maximum and no minimum: 1.85mm for 18 to 24 AWG and 1.27mm for 26 to 30 AWG. The KR3000 publishes a corridor, 1.3 to 1.8mm. So at the top end we are 0.05mm tighter than the original, and at the bottom end we impose a floor the original does not have. A thin-wall wire of 1.2mm insulation is acceptable to the original’s document and rejected by ours.

What are the mating and unmating forces?

Molex publishes 8N maximum insertion force and 2.4N minimum withdrawal force, per circuit. Our ladder is 0.80kgf (7.85N) maximum and 0.25kgf (2.45N) minimum per circuit — inside the original’s window at both ends. At the contact level Molex publishes 14.7N maximum insertion and 24.5N minimum retention, and our specification publishes 1.5kgf (14.7N) and 2.5kgf (24.5N) — the same two numbers. On wire pull-out our minimum crimp strength of 6.8 / 4.54 / 3.63kgf at 20 / 22 / 24 AWG is 66.7 / 44.5 / 35.6N, above the original’s published minimums at all three gauges.

Does the KR3000 have a TPA or a blind-mate version?

No TPA and no blind-mate version are published. Molex documents a full TPA system — 171850 and 200875 in 2 to 7 circuits, 172952 in 4 to 22 circuits, with a retainer 172953 and two TPA parts required per receptacle — and a separate blind-mate floating system with a published 2.54mm misalignment allowance and a recommended maximum mating speed of 40 mm/sec. Our wire-to-board page describes the series as “still suitable for blind mating applications” without publishing an allowable misalignment, which is worth challenging if blind mating is part of your requirement.

How many circuits does it come in?

Molex runs the dual row from 2 to 24 circuits and the single row from 2 to 12 circuits, with TPA versions narrower — 2 to 7 single row and 4 to 22 dual row. Our KR3000 documents 2 to 12 positions in single row and 2×1 to 2×12 in dual row, which covers the original’s full single-row range and its dual-row range. The TPA circuit ranges are unreachable because we publish no TPA part.

What are the housing and wafer materials?

Molex states Housing: Nylon, Header: LCP, Contact: various phosphor bronze and copper alloy, with plating at 0.25µm select tin or 0.38µm / 0.76µm select gold over nickel. Our housings are PA66 in UL94 V-0 or V-2 — and specifically Nylon66 UL94 V-2 on the wire-to-wire double-row female housing — our SMT wafer base is LCP and our DIP wafer base is PA9T, PA46 or LCP depending on part number, with phosphor bronze terminals, brass wafer pins and tin or gold over nickel plating of unpublished thickness.

What environmental tests does the Micro-Fit 3.0 require?

Thermal ageing for 240 hours at 105 ± 2°C with tin plating, or 1,000 hours at 125 ± 2°C with gold; humidity at 40 ± 2°C and 90–95% relative humidity for 96 hours; cold resistance at −40 ± 3°C for 96 hours; thermal shock and thermal cycling to 500 cycles between 15 and 85°C; salt spray for 48 hours; random vibration to EIA-364-28 condition VII; mechanical shock at 50 g half-sine for 11 ms, 18 shocks total; solderability to 95% minimum coverage; and a flowing mixed gas exposure to EIA-364-65 class 2A for 10 days unmated and 10 days mated. Contact resistance is allowed to change by no more than 20mΩ from initial after these tests. The KR3000 runs heat ageing for 96 hours, humidity for 96 hours, thermal shock for 5 cycles, salt spray for 24 hours, and a swept-sine vibration to EIA-364-28B rather than random vibration — with matching cold resistance at 96 hours and −40°C, and no thermal cycling, mixed-gas, capacitance or normal-force clauses.

What UL and CSA files does the Micro-Fit 3.0 carry?

UL file E29179 and CSA file LR19980, plus IEC 61984 certification with an NRTL type examination certificate available on request. The KR3000 component pages publish UL file E482542 only — no CSA and no IEC 61984 statement. If your approval file references a CSA registration, that is a gap to close with us before you can list the part.

Is the KR3000 a drop-in replacement for the Micro-Fit 3.0?

On fit, retention and the interface, the case is strong — 3.00mm pitch, the same 2 to 12 and 2×1 to 2×12 position ranges, matching contact resistance and insulation resistance including the test voltage, matching 30-cycle durability, matching humidity duration, and contact insertion and retention forces published as the same numbers. On three points the answer is no: the voltage rating is 250V against 600V, the wire window is 20#–24# while the original accepts 18–30 AWG, and the post-humidity insulation resistance is 100MΩ against 1,000MΩ. Treat it as a drop-in for a ≤250V, ≤5A, 20–24 AWG application and as an evaluated alternative anywhere else.

How long does it take to get samples?

Complete connector set samples within 45 days. Connector production lead time is typically 2 to 4 weeks and wiring harness lead time typically 3 to 4 weeks. For this family, say which half you need — the wire-to-board set, the wire-to-wire pair, or both — and include your wire gauge, insulation diameter and working voltage in the enquiry, because those three fields are where this cross-reference is decided.

Start Your Cross-Reference Check

KONNRA supplies the KR3000 series as individual components, crimped housing assemblies or complete cable assemblies, with customisation available for application-specific requirements.

• Request a quote — KR3000 pricing, MOQ and configuration for your circuit count and wire
• Request a sample — complete connector set samples within 45 days, wire-to-board, wire-to-wire or both
• Request cross-reference verification — confirm KR3000-to-Micro-Fit-3.0 equivalence against your specific original part number
• Request the voltage statement in writing — for any working voltage above 250V AC/DC, before you design the circuit around it
• Request the derating answer — send the gauge and the intended current and we will answer for that combination against the original’s own table
• Request the insertion and retention figures with the test basis — our §8.0 ladder gives the same figure at initial and at cycle 30, and a measured ladder is a different document
• Request the retention-force measurement method — our crimp strength clause cites no test rate against the original’s 25 ± 6 mm per minute
• Request the plating thickness — the original publishes 0.25µm tin and 0.38µm / 0.76µm gold; we publish the plating system and not its thickness
• Request the housing grade on the exact part number — our wire-to-wire double-row female housing is published as UL94 V-2
• Request the wafer resin on the exact code — DIP wafers appear as PA9T, PA46 or LCP by part number
• Request the contact wipe figure — the original publishes 1.60mm to 2.11mm depending on the mating combination and we publish none
• Request the capacitance and normal-force figures — 2pF and 2.7N on the original’s side, unpublished on ours
• Request the vibration and shock test reports — ours is a swept sine and the original’s is random vibration at condition VII, so the standard number alone does not transfer
• Request the post-humidity insulation resistance — 100MΩ is our published minimum against the original’s 1,000MΩ
• Request the panel-mount and latch-strength figures — the original publishes 155.7N panel retention and 58.0N latch yield and we publish neither
• Request the TPA answer — if your application vibrates or is assembled blind, this belongs at enquiry rather than after tooling
• Request the blind-mate misalignment allowance — our page describes the series as suitable for blind mating and publishes no allowance
• Request the crimp tooling and applicator data — terminal, applicator and hand-tool identification for the wire you are using
• Request the specification revision — PS-KR3000-01 revision A1 for wire-to-board, PS-KR3000-02 revision A1 for wire-to-wire
• Request drawings — the series drawing and the component drawing for each housing, terminal and wafer orientation you intend to buy
• Request a vendor qualification pack — certificates, test capability summary, RoHS and quality documentation
• Submit a drawing for review — we will flag any specification mismatch before you commit tooling or a board respin

Contact KONNRA Electronics

• Phone: (86)-769-85449875
• Email: info@konnra.com
• Address: No.6 Nanchang South Road, Chijiao, Wangniudun, Dongguan, Guangdong, China
• Contact us

👉 KR3000 Series Wire-to-Board product page · KR3000 Series Wire-to-Wire product page · KR3000 female terminal · KR3000 male terminal · KR3000 single row male housing · KR3000 single row right-angle DIP wafer · KR3000 DIP dual row straight wafer · KR3000 SMT dual row right-angle wafer · Molex SL 2.54 Connector Complete Guide (KR2541) · Molex MX2.0 Connector Complete Guide (KR2007) · Molex Mini-SPOX 2.50 Connector Complete Guide (KR2500) · Molex Mini50 2.0 Connector Complete Guide (KR2021) · Molex 5557 Cross-Reference (KR4200, MX4.2) · Wire-to-board connector range · Wire-to-wire connector range

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Sources and method. Every figure here is taken from a manufacturer document, and where two manufacturers — or two documents from the same manufacturer — disagree, the difference is stated rather than averaged. Molex figures come from four documents: the Micro-Fit Connectors family datasheet (987650-5984); PS-43045 revision P4 (2021/06/03, 21 sheets — Micro-Fit 3.0 dual-row connectors); PS-43650 revision N2 (2020/08/10, 20 sheets — Micro-Fit 3.0 single-row connectors); PS-44300-001 revision L3 (2016/02/17, 12 sheets — Micro-Fit BMI floating connector system); and TS-43045-001 revision A3 (2020/01/06, 10 sheets — Micro-Fit 3.0 test summary). From these: the scope statement (3.00mm pitch, wire-to-board and wire-to-wire, 18 to 30 AWG stranded copper, crimp, tin or gold); the series and part-number map (female crimp terminals 43030, 45773, 46235, 203951; male crimp terminals 43031, including the 43031-5*** TPA plug and 43031-1*** FMLB versions; housings 43025, 43020, 43645, 43640; headers 43045, 44067, 44914, 43650; TPA parts 171850, 172952, 200875, 203632, 172953; BMI parts 44133, 44300, 44428, 44432, 44764, 44769, 45280, 46622, 46623, 46625; test plug 44242; cable assemblies 45132); the safety-agency data (UL E29179, CSA LR19980, IEC 61984; agency voltage 600V; agency single-circuit currents 43020 5/7/5, 43025 8/8/5, 43045 and 44914 8/8/5, 43640 5/7/5, 43645 and 43650 8/8/5, 171850 and 200875 5/7/5); the applicable-wire table (18 to 30 AWG; maximum outside insulation diameter 1.85mm for 18–24 AWG and 1.27mm for 26–30 AWG); the current-derating tables from PS-43045 and PS-43650 (18 AWG 7/8.5, 20 AWG or 0.75mm² 6.5/7, 22 AWG 5.5/6, 24 AWG 5/5.5, 26 AWG 4/4.5, 28 AWG 3/4, 30 AWG 3/3.5 Amps for 2-circuit W-W and W-B; 30°C maximum temperature rise; reference only); the temperature table (minimum −40°C; maximum 125°C gold glow-wire, 105°C tin glow-wire, 105°C non-glow-wire; rated field temperature 65°C for 10 years per EIA-364-1000 table 8); durability 30 mating cycles; the glow-wire statement (all 43045 and 44067 headers glow-wire capable; EN 60695-2-11 / IEC 60695-2-11; EN 60335-1 / IEC 60335-1 750°C / 2 seconds; VDE report on request); the electrical requirements (contact resistance 10mΩ maximum initial at 20mV/100mA excluding wire resistance; wire-termination contact resistance 5mΩ maximum; insulation resistance 1,000MΩ minimum at 500VDC; dielectric withstanding voltage = two times the rated voltage plus 1,000 volts VAC for 1 minute, leakage <5mA in the BMI specification; capacitance 2pF maximum at 1 MHz); the mechanical requirements (normal force 2.7N minimum; pin-to-header retention 13.7N minimum in PS-43045 and 13.3N minimum in PS-44300; thumb-latch-to-ramp yield strength 58.0N wire-to-board and 45.0N wire-to-wire dual row and 68.4N single row; panel-mount retention 155.7N dual row, 89.0N 43640, 111.2N 200875, 200N in the BMI specification; compliant-pin insertion 106.7N maximum per terminal and retention 35.6N or 13.3N per terminal; connector mate and unmate forces 8.0N maximum insertion and 2.4N minimum withdrawal per circuit; crimp terminal retention 24.5N minimum; crimp terminal insertion force 14.7N maximum; wire pull-out 20 AWG 57.9N, 22 AWG 35.5N, 24 AWG 26.6N, 26 AWG 13.3N, 28 AWG 8.9N, 30 AWG 6.6N minimum in PS-44300; fretting corrosion by hammer shock at 0.98N for 20,000 cycles); the environmental requirements (fretting corrosion by thermal cycling 500 cycles between 15 and 85°C with a 0.5-hour dwell; thermal ageing 240 hours at 105 ± 2°C tin and 1,000 hours at 125 ± 2°C gold; humidity 96 hours at 40 ± 2°C and 90–95% R.H. with dielectric no-breakdown at 500VAC and insulation resistance 1,000MΩ minimum; solderability 95% minimum coverage; solder resistance 260°C maximum for both wave and reflow; salt spray 48 hours at 35 ± 2°C from a 5% solution; cold resistance 96 hours at −40 ± 3°C; corrosive atmosphere flowing mixed gas per EIA-364-65 class 2A for 10 days unmated then 10 days mated, gold-with-lubricant terminals only); the contact-wipe table (2.11mm receptacle-to-plug, 1.75mm receptacle-to-header, 1.72mm and 1.60mm for the TPA pair); the cable-tie “T” dimension table; the reflow profile parameters (preheat 150–200°C for 60 to 180 seconds, ramp 3°C/sec maximum, time above 217°C for 60 to 150 seconds, peak 260 +0/−5°C, 20 to 40 seconds within 5°C of peak, cooldown 6°C/sec maximum, 8 minutes maximum from 25°C to peak); the BMI misalignment allowance of 2.54mm and the recommended maximum mating velocity of 40 mm/sec; the material statement (Housing Nylon, Header LCP, Contact various phosphor bronze and copper alloy); the plating options (0.25µm select tin; 0.38µm and 0.76µm select gold over 2.5µm minimum tin over 1.27µm overall nickel); the environmental conformance statement (RoHS yes; halogen free yes for non-glow-wire versions); and the measured results in TS-43045-001 (initial contact resistance mean 19.95mΩ with approximately 16.6mΩ attributed to the bulk resistance of 13 inches of wire, and 4.75mΩ in the wire-to-board configuration; temperature rise and current cycling at 30 AWG 2.5A, 26 AWG 3.0A, 24 AWG 4.0A and 20 AWG 5.5A at 30°C maximum rise; wire pull-out means of 127.4N at 20 AWG, 86.1N at 22 AWG, 53.6N at 24 AWG, 36.1N at 26 AWG, 21.1N at 28 AWG and 18.2N at 30 AWG; contact normal force mean 331g with a 275g minimum requirement; and the test sequences for temperature life at 105°C for 240 hours, thermal shock at −55/+85°C, cyclic humidity at +25/+65°C, and thermal cycling at +15/+85°C for 500 hours). KONNRA figures come from PS-KR3000-01 revision A1 (2022/2/26, 8 pages — 3.00mm pitch KR3000 series wire-to-board connector specification) and PS-KR3000-02 revision A1 (2022/2/26, 7 pages — wire-to-wire connector specification), the three KR3000 product pages, the KR3000 wiring harness page, the twelve KR3000 component pages, and the KR3000 wire-to-board and wire-to-wire engineering drawings (including the male housing drawing REV A6, the female housing drawing, the female terminal drawing REV A5, and the wafer drawings REV A3). Note that the current product specifications are dated 2022/2/26 and carry edition A1, while the drawings have been revised since — the male housing drawing stands at revision A6, with a revision line recording a part-number and frame-format change and a drawing-arrangement change. Where a KONNRA figure and a Molex figure differ, both are printed side by side. Where a KONNRA document disagrees with another KONNRA document — the insulation diameter, withstanding voltage, contact resistance and insulation resistance on the wire-to-board landing page; the pitch on the wire-to-wire page; the 125°C claim on the wire-to-wire page against its own 105°C table; the temperature range on two component pages; the wire range and insulation diameter on the male terminal page; the meaning of the “Compatible” field across the housing pages; the male-terminal heading on the wire-to-board crimp table; the empty wiring harness page; and the V-0 and V-2 housing grades — the discrepancy is reported rather than smoothed over. Every force comparison in this guide is stated with its basis, because per-contact, per-circuit and whole-connector figures are not interchangeable: the original’s two per-circuit figures are a maximum and a minimum, and our two per-circuit figures were converted from the original’s newton values at 9.80665 N per kilogram-force, which is why 1.5kgf reads as 14.7N and 2.5kgf as 24.5N on both sides.