The first question has to come first, because 1.50mm is a pitch, not a connector. Molex alone runs at least three different 1.50mm wire-to-board systems — Pico-SPOX, CLIK-Mate and Micro-Lock Plus — and none of them mate with each other. Get the series number off the drawing before you cross-reference anything.
And there is a fourth name you should not trust: "Micro SPOX" does not appear as a Molex product family. Molex's own wire-to-board listing carries Mini-SPOX (2.50mm) and Pico-SPOX (1.50mm) in the SPOX class — nothing called "Micro SPOX". The label shows up in distributor listings. Treat it as unverified until you confirm the pitch and series number on the manufacturer's documentation.
Once you know it is a Pico-SPOX, the second question has a clear answer. The KONNRA KR1500 is documented as the cross-reference equivalent, component by component — nine separately orderable parts, matching 1.50mm pitch, 250V, 500V AC withstanding voltage, 20mΩ contact resistance and 1000MΩ insulation resistance. It is not a blanket drop-in; three things have to be settled first, and they are the same three things that go wrong on this connector.
I work on connector and harness programmes at KONNRA, which publishes that cross-reference. Here is what actually decides the answer.
First: sort the three 1.50mm systems
Pico-SPOX is a crimp wire-to-board system: a crimp terminal, a receptacle housing and a PCB header. Retention is a friction lock with polarization keys — there is no latch to release.
CLIK-Mate is the positive-latch system with an audible click, offered at 1.25, 1.50 and 2.00mm. Molex positions it for blind mating and for lines where the operator cannot see the connector seat. It is not a drop-in for a Pico-SPOX: it changes the header envelope, the mating force and the housing.
Micro-Lock Plus is Molex's enhanced-locking system, also offered at 1.25, 1.50 and 2.00mm.
And do not fold Pico-SPOX into PicoBlade. PicoBlade is 1.25mm, and covers both wire-to-board and wire-to-wire. It is a different pitch and a different family. (Worth knowing: Molex's PicoBlade family page says "up to 3.0A / up to 250V", while its own product specification states 1.0A and 125V. On this family the specification is the document to quote from.)
The fastest way to separate them is the retention mechanism, not the pitch. A friction lock with no latch to release is Pico-SPOX. A latch that clicks is CLIK-Mate.
The second fastest way is the contact. A spring-box terminal with two inward-facing grooves is the Pico-SPOX signature — the box grips the header pin at two points. A single-point contact at this pitch indicates a different series.
One more naming trap, and it is on the second-source side. KONNRA runs three series at or near 1.50mm, and they are three different products:
- KR1500 — the Molex Pico-SPOX equivalent. Your answer if the original is a Pico-SPOX or "MX1.5".
- KR1501 — the JST ZH 1.5mm equivalent. Same nominal pitch, different original manufacturer, different mating interface, not interchangeable with a Pico-SPOX.
- KR1507 — the Molex CLIK-Mate equivalent, a positive-latch system. Note its documented ratings are single row 3A / 100V and dual row 1.5A / 100V, against Molex's "up to 250V" family figure — so if your circuit runs above 100V, settle that number first.
A quotation that offers "a 1.50mm equivalent" without naming which of the three it is has not answered the question.
What the Pico-SPOX actually is
It is Molex's 1.50mm-pitch, single-row, wire-to-board system, documented as saving 30% of the space of a 2.00mm-pitch wire-to-board connector at the same circuit count. Molex publishes it in vertical and right-angle orientations across 2 to 15 circuits, and positions it for compact consumer devices, vehicles, appliances, industrial equipment and medical equipment.
Documented parameters:
- 1.50mm pitch, single row, 2 to 15 circuits
- 250V AC (RMS)/DC allowable voltage
- Rated current per wire gauge: 2.5A at AWG #24, 2.0A at #26, 1.5A at #28 and #30
- Reference derating table published by gauge and circuit count, up to 3.5A at 2 circuits
- 500V AC (RMS) one-minute dielectric withstanding voltage
- 1000MΩ minimum insulation resistance, 20mΩ maximum contact resistance (5mΩ max on the crimped portion; 40mΩ max after environmental exposure)
- −55°C to +105°C, including terminal temperature rise
- 10-cycle durability on gold-plated parts
- Spring-box terminal with two inward-facing contact grooves
- Friction lock plus polarization keys
- 30°C maximum temperature rise (to UL498)
- UL File E29179 Vol.10 and CSA File LR 19980-367
- RoHS compliant; Molex lists the family as not low-halogen
The three things to settle before a cross-reference is signed off — and the honest answer on each:
1. The current rating is a ladder, and the second-source web page shows a flat number. This is the parameter most often quoted wrong. Molex's product specification gives 2.5A at AWG #24, 2.0A at #26 and 1.5A at #28 and #30. The KR1500 product specification gives 2.5A (24 AWG) — consistent at that gauge — while the KONNRA web specification table presents a flat 2.5A with no gauge qualifier.
At AWG #24 nothing needs resolving; the two agree. Below AWG #24 the published flat figure is optimistic. A design drawing that reads "2.5A" on an AWG #28 harness is 67% above Molex's allowable current for that gauge, which is 1.5A. State the gauge every time.
And if you are about to quote the headline: Molex's product page and family listing say "up to 3.5A." That figure is real — and it is also the top of a reference table: 3.5A is a 2-circuit, AWG #24 number at a 30°C temperature rise with all circuits powered, and Molex marks the table for reference only and states that PCB trace design can greatly affect temperature rise results. It is not the rating for your 12-circuit connector on AWG #28.
2. The KONNRA page quotes three different current figures for the same series. The web specification table says 2.5A; the web Overview text says "up to 2.5A"; the web "Compact Design" advantages text says "a system rating of 3.0 A."
For context, Molex's own maxima are 2.5A at AWG #24 for the LCP headers (78047 / 78048) and 3.5A at AWG #24 for the Nylon headers (87437 / 87438) — so neither KONNRA figure equals the higher Molex number, and 3.0A matches nothing on either side. Pick one figure, in writing, before it goes on a drawing.
3. The withdrawal force is the largest mechanical difference on the series — and it is about retention, not mating effort. Both documents publish a force table by circuit count, in kilogram-force on the KONNRA side and newtons with a kgf equivalent on the Molex side:
- 2 circuits: Molex 9.8N (1.0 kgf) min vs KONNRA 0.2 kgf (2.0N) min
- 5 circuits: Molex 9.8N (1.0 kgf) min vs KONNRA 0.5 kgf (4.9N) min
- 8 circuits: Molex 15N (1.5 kgf) min vs KONNRA 0.8 kgf (7.8N) min
- 10 circuits: Molex 15N (1.5 kgf) min vs KONNRA 1.0 kgf (9.8N) min
- 15 circuits: Molex not documented in the material reviewed; KONNRA 1.5 kgf (14.7N) min
At 2 circuits those differ by roughly a factor of five. The insertion force maxima, by contrast, track closely — KONNRA specifies 2.50 kgf (24.5N) max at 2 circuits and Molex specifies 25N (2.5 kgf) max. So the divergence is specifically in retention.
That matters more on this connector than on most, because the friction lock is the only retention mechanism on a Pico-SPOX. There is no latch to share the load. Test it on your own samples rather than inferring it from either document.
Six more points to verify before you sign off
These are the places the two documents do not say the same thing — or where one of them says nothing.
1. Operating temperature is 15°C narrower at the cold end on the second-source side. Molex documents −55°C to +105°C in both its tin-plating and gold-plating specifications, and runs its cold test at −55±3°C for 96 hours. The KR1500 is documented at −40°C to +105°C, with a cold test at −40±2°C for 96 hours. The hot end matches; the cold end does not. If your product is qualified to −55°C, the KR1500 as documented does not cover it — that is a specification gap, not a test-report gap.
2. Durability runs the other way: 10 cycles on the Molex side, 30 cycles on the KONNRA side. Molex specifies 10 cycles durability (gold-plated) and a repeated insertion/withdrawal test of 10 cycles. The KR1500 product specification specifies 30 cycles at no more than 10 cycles per minute, referenced to EIA-364-09C. A threefold claim against the original is a claim to verify rather than an equivalence to assume — the reference standards differ, so the two numbers are not directly comparable. Note also that the KONNRA web page publishes no cycle count at all; the 30-cycle figure exists only in the specification PDF.
3. The insulation resistance disagrees with itself on the second-source page, but the authoritative document agrees with Molex. The KONNRA web specification table says 1000MΩ min, and the product specification §5.2 says 1000 Megohms Min. — identical to Molex's 1000MΩ min. The outlier is the web Overview prose, which says "high insulation resistance (min. 100MΩ)". Separately, KONNRA's product specification §7.7 requires only 100 Megohms Min. after the humidity test — a post-conditioning floor, not the base specification. Quote 1000MΩ for the unmated baseline and 100MΩ as the post-humidity floor if your programme needs it.
4. The applicable wire range stops at AWG #28 on the KONNRA side. Molex's range is AWG #24 to #30, split across two terminal families. The KR1500 product specification states applicable wire AWG 24# to 28#, and the web entry says 24-28 AWG. AWG #30 is outside the published KR1500 range. It is the finest and least current-capable gauge in the family — 1.5A, with the lowest crimp pull-out force — so the practical risk is low, but raise it rather than assume it.
5. The insulation diameter window is one band on one side and two windows on the other. Molex's machine specification allows φ0.70 to 1.15mm, but its two terminal families are individually qualified at 0.70–1.00mm (the #30–26 terminal) and 0.95–1.20mm (the #26–24 terminal). KONNRA publishes 0.7 to 1.1mm as a single band across the series. So a cable with 0.9mm insulation passes the Molex machine window, sits outside the Molex lighter-wire terminal's window, and sits inside KONNRA's band. The same wire is acceptable on one side and not the other depending on which terminal is fitted. Check both ends against the actual terminal, not the family figure.
6. Two structural differences. Mounting: KONNRA documents SMT wafers only — labelled SMT 180° (straight) and SMT 90° (right angle) — while Molex lists both SMT and through-hole headers. If your design needs a through-hole header, that configuration is not documented for the KR1500. Agency approvals: Molex cites UL File E29179 Vol.10 and CSA File LR 19980-367; the KONNRA product specification carries no agency file numbers. Request the file reference if your qualification requires UL recognised status for the specific part.
And one parameter that needs no action, but is worth recording because it looks wrong and is not. The dielectric withstanding voltage agrees at 500V AC for one minute on both sides. This matters because the KONNRA page also carries a 250V figure — and 250V is also the rated voltage, which would be a red flag if the withstanding field had been filled with the rating by mistake. It has not been. KONNRA's General Specification table states 500V AC/minute, the Overview text repeats it, and product specification §5.3 states "apply 500V AC for 1 minute between adjacent terminal or ground … No Breakdown and Flashover." Molex's PS-87437-001-001 §5-1-3 states "apply 500V AC (rms) for 1 minute … No Damage on function." Same test potential, same duration, same pass criterion. The 250V is the working voltage; the 500V is the proof test. Record both, and do not swap them on a drawing.
Components and configuration
The KR1500 is specified as nine separately orderable components — six wafers, two housings and a terminal — which is what lets one series serve straight and right-angle SMT designs with and without an extra buckle feature:
- Right Angle Wafer — SMT 90°
- Right Angle Wafer Have Buckle
- Right Angle Wafer Have Buckle B
- Straight Wafer — SMT 180°
- Straight Wafer Have Buckle
- Straight Wafer Have Buckle B
- Housing — the cable-side receptacle
- Housing Have Buckle
- Terminal — crimp contact for AWG #24 to #28
Two notes on that range. The wafer base is documented as LCP, UL94 V-0, with brass contacts and a brass solder tab, and no separate Nylon-header option is published — so if your layout was qualified against a Molex Nylon header (87437 / 87438) rather than an LCP one (78047 / 78048), name the body material on the enquiry. And the "Have Buckle" and "Have Buckle B" variants are KONNRA additions that do not appear as distinct entries in Molex's Pico-SPOX ordering table: if your design relies on the plain friction lock, order the plain wafer.
On the part numbers, which carry more information than the family name. KONNRA's product specification assigns internal part numbers by functional group: housing H150001****01A and H150001****02A; terminal T15000PG0101A (gold) and T15000PT0101A (tin); wafer C1500RS1*********RA (right angle) and C1500VS1*********RA (straight). Note the logic: RS is right angle, VS is straight, and the PG / PT suffix distinguishes gold from tin. That is the check to run when a BOM line reads only "KR1500 terminal" — the plating is in the part number, not the family name.
And the molex side splits the terminal four ways, which the family name does not show. Molex's Pico-SPOX terminal (87421) covers two wire ranges in two finishes:
874210100— AWG #30–26, pre-plated tin 2.540µm, insulation O.D. 0.70–1.00mm874210102— AWG #30–26, gold 0.100µm min (nickel barrier 1.270µm), 1.00mm max874210000— AWG #26–24, tin 2.540µm, 0.95–1.20mm874210002— AWG #26–24, gold 1.000µm min, 0.95–1.20mm
The two families overlap at AWG #26, and there the plating spec decides as much as the wire — all four terminals carry the same headline ratings. Note also that the gold thickness is not one number: the lighter-wire gold terminal is specified at 0.100µm minimum and the heavier-wire one at 1.000µm minimum, a tenfold difference. A BOM line reading simply "gold plated" records none of that, and the KONNRA documentation does not state a thickness at all — so if your qualification names one, raise it.
One inconsistency inside the Molex documents themselves, worth knowing. The current rating quoted in Molex's Pico-SPOX summary datasheet is not the same for all four headers: it lists 2.5A max (AWG #24) for the 78047 / 78048 LCP headers and 3.5A max (AWG #24) for the 87437 / 87438 Nylon headers. The product specification's per-gauge figures — 2.5A at #24 — are the conservative set. That is exactly why the gauge-specific ladder, not the family headline, is the one to work from.
Design and process notes that account for most field problems
Clean up the current-derating thinking first. Molex's published table assumes all circuits powered — the worst case — measured in the barrel area of the crimp terminal, at a 30°C temperature rise, on a specific test board, and Molex states plainly that PCB trace design can greatly affect temperature rise results. A design that passes on two circuits will not necessarily pass on fifteen. If you need more than the 2.5A allowable at AWG #24, the number to work from is your own temperature-rise test on your own board.
Tie the cable down; do not hang the harness from the connector. With no positive latch, the correct retention answer is a cable tie or a strain-relief feature on the harness — not the friction lock. At 2 circuits the withdrawal minimum is specified at 0.2 kgf (2.0N) on the second-source document. A friction lock of that order keeps a mated pair together; it does not carry a cable load.
Check the polarity key engagement as part of the build instruction. Both descriptions rely on polarization keys to prevent mis-mating. A key that is not engaged means the housing is not seated, and the friction lock alone will not hold it.
Watch the solder-joint stress on SMT headers. A 1.50mm-pitch SMT header carries real insertion and withdrawal forces — up to 7.0 kgf (68.6N) insertion at 15 circuits on the KONNRA document. Solder-tab retention is specified at 9.8N (1.0 kgf) minimum on both sides, which is the number to design against if the harness will be pulled.
Do not reflow past the documented profile. The KR1500 product specification §9.0 gives a 255±5°C peak for 5–10 seconds, a minimum of 230°C, and a 150–200°C preheat, and notes the condition changes with the soldering device and the PCB. Molex qualifies its SMT headers to three IR reflow passes, and allows 350±5°C for 5 seconds maximum with a soldering iron.
Crimp settings are gauge-specific, not one family setting — this is unusually well documented on the KONNRA side and it is what your harness house should be crimping to:
- AWG #24 — conductor crimp height 0.70±0.05mm, insulation crimp height 1.45mm max, crimp strength 3.63 kgf min, strip length 1.2–1.6mm
- AWG #26 — 0.65±0.05mm, 1.40mm, 2.27 kgf, 1.2–1.6mm
- AWG #28 — 0.55±0.05mm, 1.25mm, 1.36 kgf, 1.2–1.6mm
- Conductor crimp width 0.9–1.0mm; insulation crimp width 1.15mm max
KONNRA's minimum crimp strength is higher than Molex's crimp pull-out minimum at the same gauges (3.63 vs 3.0 kgf at #24, 2.27 vs 2.0 kgf at #26, 1.36 vs 1.0 kgf at #28) — but the two are tested to different standards, so treat that as encouraging rather than equivalent.
Plan a new housing after terminal extraction. Extracting a crimp terminal deforms the housing lance, which is the feature that holds the terminal. Fitting a new housing after extraction is the safe assumption here.
And the pick-and-place question, if the board runs through an SMT line. Molex offers SMT headers with a pick-and-place cap, specified at 0.49N (50gf) minimum cap retention. The KONNRA documentation does not describe an equivalent placement feature. If your nozzle needs a flat top, raise it before tooling.
What it is not for. At 2.5A at AWG #24 — and only 1.5A at AWG #28 and #30 — the Pico-SPOX is a small-power and signal interface, not a power connector. And although Molex cites a "no nail function", a 1.50mm-pitch friction-lock pair is not a board-to-board retention system: do not design a service procedure or a cable route that loads the mated pair.
What to send for a cross-reference check
Most MX1.5 enquiries stall on the same thing: the buyer is not sure what the supplier needs, so the enquiry never gets sent. This is the complete list.
- The original part number, if you have it — a housing such as
87439****, a terminal such as874210000, or a header such as87437**** - Circuit count — the range is 2 to 15
- Wire gauge, and specifically whether it is AWG #28 or #30 — Molex's allowable current is 1.5A at both, while the KONNRA web page shows a flat 2.5A
- Insulation outside diameter, not just the gauge — Molex allows φ0.70–1.15mm in the machine specification but only 0.70–1.00mm on the lighter-wire terminal; KONNRA publishes 0.7–1.1mm
- Plating finish required — tin or gold, and if gold, at what thickness
- Mounting and orientation — straight or right-angle, and confirm whether you need through-hole, because KONNRA documents SMT only
- Whether the design needs a buckle variant — the "Have Buckle" and "Have Buckle B" wafers are KONNRA additions, so say which one your retention strategy relies on
- Your load current per circuit and the number of circuits carrying it, so the gauge-specific allowable current and the derating position can be settled rather than assumed
- Minimum operating temperature, if your product goes below −40°C
- Application and annual volume
- A drawing or photo if the part number is unreadable or the design has been reverse-engineered
When you send a part number, four things get confirmed against Molex's own documentation: the terminal that matches your wire gauge and insulation diameter, the plating and its thickness, the header orientation and mounting type, and whether your design needs the plain friction-lock wafer or a buckle variant. Those four are where an MX1.5 cross-reference most often goes wrong.
What you get back: a mapped KR1500 part number with the relevant product and engineering drawings, a specification comparison against your original part, and a sample and quote plan.
And one candid note about the documents. Every "not documented" above is a gap in the documentation reviewed, not a statement that the property does not exist. Molex publishes a product specification with full electrical, mechanical and environmental tables — PS-87437-001-001 Rev G for tin-plating and 2027051000-PS-000 Rev B for gold-plating — and KONNRA publishes PS-KR1500-01. Where a figure could not be traced to one of those, it is left open rather than filled from a third-party aggregator. The environmental severities are the clearest example of that gap, and they are covered next.
A note on the environmental test data, because it is not interchangeable
The acceptance limit after environmental exposure is identical on both sides — 40mΩ max contact resistance — but the exposures are not the same, and the differences are large enough that the two do not evidence each other:
- Heat resistance: Molex 105±2°C for 168 hours vs KONNRA 105±2°C for 96 hours
- Cold resistance: Molex −55±3°C for 96 hours vs KONNRA −40±2°C for 96 hours
- Humidity: Molex 85±2°C / 85±3% RH for 168 hours vs KONNRA 40±2°C / 90–95% RH for 96 hours
- Temperature cycling: Molex −55°C / +105°C, 2 hours each, 10 cycles vs KONNRA −40°C / +105°C, 30 minutes each, 5 cycles
- Salt spray: Molex 48±4 hours vs KONNRA 24 hours, both at 35±2°C, 5±1% NaCl
- Vibration: Molex 1.52mm P-P, 10–55–10Hz, 2 hours per axis vs KONNRA 1.5mm P-P, same sweep, 2 hours per axis
- Mechanical shock: Molex 490 m/s² (50G), 11ms, 18 shocks vs KONNRA 490 m/s² (50G), 3 strokes per axis
- Solderability: both at 245±5°C — Molex 5±0.5 seconds, KONNRA 3±0.5 seconds
The humidity test is the widest gap. 85°C / 85% RH is a materially harsher exposure than 40°C / 90–95% RH, and if your qualification calls up an 85/85 humidity test, the KR1500 document does not evidence it as written. That is worth raising on the enquiry rather than discovering at qualification.
About KONNRA
Dongguan Konnra Electronics Co., Ltd. (brand: KONNRA) was founded in 2004 and is a National High-Tech Enterprise specialising in connector and wiring harness research, development, production and sales. Manufacturing is vertically integrated — precision mould design and manufacturing, precision injection moulding, stamping, assembly and CCD visual inspection — with automation coverage exceeding 95% across production lines. Testing runs through a CNAS-accredited laboratory with 45+ sets of precision testing instruments.
Quality systems: ISO9001, ISO14001, IATF16949, ISO45001:2018, ISO13485, IPC620, and UL product and operational safety certifications, with automotive-grade series additionally certified to LV214 and US CAR-2. Complete connector set samples can be delivered within 45 days; connector production lead time is typically 2–3 weeks and wiring harness lead time typically 3–4 weeks. Harness assemblies are built in the standard configurations, including adapter and transition cables where one end is a Pico-SPOX and the far end is, for example, a 1.50mm JST ZH or a 1.00mm interface.
Where a standard part does not fit — an AWG #30 path, a specific gold thickness, a non-standard harness length, a buckle variant, or a transition to another interface — KONNRA supports customer joint R&D customisation.
Contact KONNRA Electronics
- Phone: (86)-769-85449875
- Email: info@konnra.com
- Address: No.6 Nanchang South Road, Chijiao, Wangniudun, Dongguan, Guangdong, China
- Contact us
View the KONNRA KR1500 MX1.5 (Pico-SPOX) Connector
https://konnra.com/molex-pico-spox-connector-complete-guide/
Dongguan Konnra Electronics Co., Ltd
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