JST XH 2.5 Connector Complete Guide: Specs, Pin Counts, the 2.5mm Pitch Class & the KONNRA KR2501 Equivalent

Quick answer: The JST XH connector is a 2.5mm pitch, single-row, wire-to-board crimp connector with a friction lock and a box-shaped shrouded header. It is rated 3A AC/DC at 250V AC/DC, mates at a 9.8mm mounting height, and accepts AWG #30 to #22 (0.05–0.33mm²) with insulation O.D. from φ0.9mm to φ1.9mm. JST supplies three crimp terminals for it — SXH-001T-P0.6 for AWG #28–#22, SXH-002T-P0.6 for AWG #30–#26, and SXH-001T-P0.6N, a low-insertion-force contact for AWG #26–#22. JST documents housings from XHP-1 through XHP-16, plus XHP-20. The KONNRA KR2501 series is documented as its cross-reference equivalent, covering 2 to 16 circuits in through-hole (DIP) and SMT, straight and right-angle.

The XH is the connector most people meet first. It is the 2.5mm family that ended up on hobby batteries, 3D printer mainboards, appliance control panels, and industrial I/O modules — not because it is the smallest or the cheapest, but because it is the smallest pitch in JST’s range that still carries 3A at 250V with a positive friction lock and a fully shrouded header. It was developed from JST’s NH series, and JST documents the header as interchangeable with the NR and NRD insulation-displacement connectors and the JQ board-to-board connector, so one PCB footprint can carry three different termination systems. That range — 2.5mm through 3A/250V — is also where the confusion starts. Three JST families share the 2.5mm pitch (XH, EH and XA), and they do not mate with each other. The XH is additionally sold under the label “2.54mm” in a large part of the trade, which is not the pitch JST specifies. And the family’s wire range is published in three different places as three different numbers, depending on whether the writer is quoting the series, one terminal, or one terminal’s insulation window. This guide is built the other way round: every JST figure below comes from JST’s published XH documentation, every KONNRA figure from KONNRA’s product documentation, and every disagreement is stated rather than smoothed over.

A note on naming: this part appears as JST XH 2.5 connector, JST XH2.5, XH 2.5mm, XH2.54, “2.5mm JST connector”, and “2.54mm JST connector” in listings and searches. The connector JST documents as the XH runs at a 2.5mm pitch. This guide also cross-references the KONNRA KR2501 series, which KONNRA documents as the XH 2.5 equivalent.

What this guide covers:

• Verified JST XH and KONNRA KR2501 specifications side by side
• Complete part number cross-reference — housings, headers, terminals, packaging options
• Which of the three SXH terminals goes with which wire, and where their ranges overlap
• The 2.5mm pitch is 2.5mm — where the “2.54mm” label comes from and when it matters
• The specification differences to check before you cross-reference
• Through-hole and SMT options, and why the SMT range is narrow
• Sourcing questions procurement teams ask (lead time, samples, qualification docs)
• How to get a cross-reference check on your specific part number

Key Specifications at a Glance

Attribute	JST XH 2.5	KONNRA KR2501
Pitch	2.5mm	2.5mm
Termination	Crimp (SXH-001T-P0.6 / SXH-001T-P0.6N / SXH-002T-P0.6)	Crimp
Mounting	Through-hole and SMT (SMT listed for 3, 4 and 6 circuits)	DIP and SMT, straight and right-angle
Current rating	3A AC/DC (AWG #22)	3A
Voltage rating	250V AC/DC	250V
Circuits	XHP-1 – XHP-16 and XHP-20 housings; headers 2–16 and 20	2 – 16
Wire size	AWG #30 – #22, by terminal	See specification section
Insulation O.D.	φ0.9 – 1.9mm (terminal-dependent)	1.2 – 1.8mm
Mated height	9.8mm	9.8mm
Lock	Friction lock	With lock (friction)
Operating temperature	−25°C to +85°C	−40°C to +105°C
Contact resistance	10mΩ max initial; 20mΩ max after environmental tests	20mΩ max
Insulation resistance	1,000MΩ min.	1,000MΩ min.
Withstanding voltage	1,000 VAC / minute	250V AC / minute (see the note below)
Housing material	PA 6, UL94V-0, natural (white)	PA9T / LCP / UL94
Header material	Post: brass, copper-undercoated, tin-plated (reflow treated). Wafer: PA 66, UL94V-0 (glass-filled PA 66 on the -2 type; PA 6T on the SMT type)	Brass
Plating	Tin-plated (reflow treatment)	Tin over nickel
Standards	UL, CSA, TÜV (Recognized E60389); RoHS2	UL certification; RoHS compliant

Both columns are compiled from manufacturer documentation, not distributor listings. Sources are listed at the end of this guide.

What Is the JST XH 2.5 Connector?

The JST XH is a 2.5mm pitch, single-row, wire-to-board crimp connector. A wire is crimped into a terminal, the terminal clicks into a housing, and the housing latches onto a shrouded header on the PCB with a friction lock. A complete connection uses three parts:

• XHP housing — the wire-side plug, from 1 to 16 circuits or 20
• B…B-XH or S…B-XH header — the PCB-side shrouded header, top entry or side entry, through-hole or SMT
• SXH terminal — the crimp contact, selected by wire size and insulation diameter

Key characteristics:

• 2.5mm pitch — JST’s highest-current single-row wire-to-board family before the 3.96mm class
• 3A per contact at 250V AC/DC — rated with AWG #22 wire, and the highest rating in JST’s compact crimp range
• Friction lock — JST specifies a friction lock rather than a lance-and-window latch, and the housing is polarized so it seats in one orientation only
• Box-shaped shrouded header — the header is fully boxed, so the contacts are protected and the mating housing is guided into place
• Developed from the NH series — JST states the XH was developed based on the reliability of its NH series connectors
• Interchangeable header — JST documents the XH header as interchangeable with the NR and NRD insulation-displacement connectors and the JQ board-to-board connector
• Original folded beam contact — the terminal uses a folded beam rather than a simple cantilever, which JST specifies for contact stability
• 9.8mm mounting height — described by JST as low profile for this pitch class
• Header with a boss available — a locating boss version exists for placement and mechanical location
• Through-hole and SMT — but SMT is catalogued only for 3, 4 and 6 circuits
• Colour options — natural white as standard, with red, blue, yellow, lemon yellow, green, orange, brown, black and fluorescent yellow available

Figure 1 — KONNRA KR2501 series: 2.5mm pitch XH wire-to-board connector with friction lock

➡️ View the KONNRA KR2501 XH 2.5mm Connector

JST XH 2.5 = KONNRA KR2501: Part Number Cross-Reference

JST XH component	JST part number	KONNRA equivalent
Wire housing, 1–16 and 20 circuits	XHP-1 … XHP-16, XHP-20	KR2501 Housing (2–16 circuits)
Through-hole header, top entry	B2B-XH-A … B16B-XH-A, B20B-XH-A	KR2501 DIP straight 180° wafer
Through-hole header, side entry	S2B-XH-A … S16B-XH-A (add -1 for the 7.6mm end-face-to-post version)	KR2501 DIP right-angle 90° wafer
SMT header, side entry with solder tab	S3B-XH-SM4-TB, S4B-XH-SM4-TB, S6B-XH-SM4-TB	KR2501 SMT right-angle 90° wafer
Top-entry header, glass-filled nylon	B2B-XH-2 … B15B-XH-2	KR2501 DIP straight 180° wafer
Top-entry header with boss	B1B-XH-AM, B2B-XH-AM … B12B-XH-AM	KR2501 DIP straight 180° wafer
Header on radial tape	B3B-XH-TV4, B4B-XH-TV4; B2B-XH-2-TV4 … B8B-XH-2-TV4	—
Crimp terminal, widest wire range	SXH-001T-P0.6 — AWG #28–#22 (0.08–0.33mm²), insulation 0.9–1.9mm	KR2501 Terminal
Crimp terminal, fine wire	SXH-002T-P0.6 — AWG #30–#26 (0.05–0.13mm²), insulation 0.9–1.3mm	KR2501 Terminal
Crimp terminal, low insertion force	SXH-001T-P0.6N — AWG #26–#22 (0.13–0.33mm²), insulation 1.3–1.9mm	—
Compatible IDC and board-to-board on the same header	NR / NRD IDC connectors; JQ board-to-board connector	—

Reading the part numbers. The circuit count is embedded in the position digits: XHP-4 is the 4-circuit housing, B4B-XH-A is the 4-circuit top-entry through-hole header, S4B-XH-A is the 4-circuit side-entry header. The A suffix indicates a clinched post. A -2 after XH denotes the glass-filled nylon wafer (for example B4B-XH-2), -AM denotes the top-entry header with a locating boss, and -SM4-TB denotes the SMT type with a solder tab supplied on embossed tape. On the terminal side, S means strip form and B means loose piece, P means phosphor bronze, and T means tin-plated with reflow treatment.

The three XH terminals, and where their ranges overlap

This is the part of the XH documentation that gets compressed most often, because the three terminals are not a clean split.

Terminal	Wire range	Insulation O.D.	Use it for
SXH-001T-P0.6	AWG #28 to #22 (0.08 to 0.33mm²)	0.9 to 1.9mm	The default XH terminal — widest conductor and insulation window
SXH-002T-P0.6	AWG #30 to #26 (0.05 to 0.13mm²)	0.9 to 1.3mm	Fine wire — thin signal runs, small-gauge harnesses
SXH-001T-P0.6N	AWG #26 to #22 (0.13 to 0.33mm²)	1.3 to 1.9mm	Low-insertion-force contact — easier mating, less resistant to vibration

Two things follow from this table, and both matter. First, the series range is AWG #30 to #22 — not #28 to #22. JST states the XH’s applicable wire as AWG #30 to #22, which is the union of the three terminals. If a specification sheet or a comparison table quotes the XH family at AWG #28–#22, it is quoting the SXH-001T-P0.6 terminal alone, not the series. That matters when a drawing is written against the series range but the part actually specified is the 001. Second, the 001 and 002 terminals overlap on AWG #26–#28. A conductor in that band can be crimped into either one. What decides it is not the conductor but the insulation outside diameter: SXH-002T-P0.6 stops at 1.3mm, so wire with insulation above 1.3mm has to go into an SXH-001T even though the conductor fits the 002. Select the terminal by conductor size first, then confirm the insulation diameter is inside that terminal’s window — not the series window. On the low-insertion-force option. JST documents SXH-001T-P0.6N as a low-insertion-force contact for easier insertion and withdrawal, and states plainly that it is less resistant to vibration. That is a trade, not a free upgrade. In a vibration environment — a printer gantry, a power tool, an appliance with a compressor — the standard 001 or 002 contact is the appropriate choice.

One header, three connection systems

JST documents the XH header as interchangeable with the NR and NRD insulation-displacement connectors and with the JQ board-to-board connector. In practice that means the same shrouded header footprint on the PCB can be built three ways: crimp termination (XH), insulation-displacement termination (NR/NRD), or a board-to-board stack (JQ). For a programme that moves from bench crimping to factory-built IDC assemblies, the board does not have to change. KONNRA does not document an NR, NRD or JQ equivalent against the KR2501, so if your design depends on that interchangeability, confirm it before switching.

The friction lock is the XH’s mechanical identity. Unlike the lance-and-window system on the smaller ZH and SH families, the XH relies on friction between the housing and the shrouded header. That is what makes the 9.8mm-high box header worth its board area — the shroud carries the retention load, not the terminals.

JST XH 2.5 / KONNRA KR2501 Specifications

Parameter	JST XH 2.5 (JST documentation)	KONNRA KR2501 (KONNRA documentation)
Pitch	2.5mm	2.5mm
Row configuration	Single row	Single row
Connection type	Wire-to-Board	Wire-to-Board
Termination	Crimp (SXH-001T-P0.6 / SXH-001T-P0.6N / SXH-002T-P0.6)	Crimp
Current rating	3A AC/DC (AWG #22)	3A
Voltage rating	250V AC/DC	250V
Circuits	XHP-1 – XHP-16 and XHP-20 housings	2 – 16
Conductor size	AWG #30–#22 (0.05–0.33mm²), by terminal	—
Insulation O.D.	φ0.9–1.9mm (terminal-dependent: 0.9–1.3 / 0.9–1.9 / 1.3–1.9)	1.2 – 1.8mm
Contact resistance	10mΩ max initial; 20mΩ max after environmental tests	20mΩ max
Insulation resistance	1,000MΩ min.	1,000MΩ min.
Withstanding voltage	1,000 VAC for one minute, no breakdown or flashover	250V AC / minute
Operating temperature	−25°C to +85°C (including temperature rise under load)	−40°C to +105°C
Mated height	9.8mm	9.8mm
Applicable PC board thickness	1.6mm	—
Housing material	PA 6, UL94V-0, natural (white)	PA9T / LCP / UL94
Header material	Post: brass, copper-undercoated, tin-plated (reflow treated). Wafer: PA 66, UL94V-0 (glass-filled PA 66 on the -2 type; PA 6T on the SMT type)	Brass
Contact material	Phosphor bronze, tin-plated (reflow treatment)	—
Plating	Tin-plated (reflow treatment); gold-plated or brass contacts on request	Tin over nickel
Mounting	Through-hole top and side entry; SMT side entry (3, 4 and 6 circuits)	DIP 90° / 180° and SMT 90° / 180°
Lock	Friction lock	With lock (friction)
Packaging	Radial tape (TV4); embossed tape for the SMT type	Tape and reel (see package specification)
Standards	UL, CSA, TÜV (Recognized E60389); RoHS2	UL certification; RoHS compliant

” — ” indicates the parameter is not stated in the manufacturer documentation reviewed for this guide. Confirm any blank against the current JST XH datasheet before releasing a drawing.

Specification differences worth verifying before you cross-reference

Seven points deserve attention before you sign off a cross-reference.

1. Withstanding voltage differs by a factor of four — 250V AC/minute on the KR2501 versus 1,000 VAC/minute on the JST XH. This is the one parameter where the JST part is documented to a substantially higher figure. JST specifies the XH at 1,000 VAC applied for one minute with no breakdown or flashover. KONNRA documents the KR2501 at 250V AC per minute. Note that 250V is also the KR2501’s rated voltage, which raises the question of which test the KONNRA number describes — a rated-voltage withstand, or the dielectric breakdown test JST is quoting. If your specification, your customer, or a safety standard requires a 1,000 VAC withstand, raise it with KONNRA engineering before you qualify the part rather than after.

1. The temperature range is wider on the KR2501. JST documents the XH at −25°C to +85°C, including temperature rise under load. KONNRA documents the KR2501 at −40°C to +105°C. A wider claim needs backing: if your application actually relies on operation above +85°C, ask for the test data rather than taking the number at face value.

1. The insulation diameter window is narrower on the KR2501. JST’s XH terminals accept insulation from φ0.9mm to φ1.9mm depending on which terminal you select. KONNRA documents the KR2501 at 1.2–1.8mm. Note this is narrower at both ends: the standard SXH-001T-P0.6 terminal accepts 0.9mm insulation that the KR2501 figure excludes, and only the low-insertion-force 001N reaches 1.9mm. If your harness uses thin-walled or heavy-walled wire at the ends of the range, confirm the accepted dimensions against the KR2501 product specification.

1. Contact resistance — compare like with like. JST publishes two maximums for the XH: 10mΩ initial and 20mΩ after environmental tests. KONNRA documents the KR2501 at 20mΩ max, which is the same figure as JST’s after-test value. A table that compares KONNRA’s 20mΩ against JST’s 10mΩ initial figure is comparing a new part against an aged one. If contact resistance is critical, request the test data from both sources.

1. Housing and wafer materials are different polymers. JST documents the XHP housing as PA 6, UL94V-0, natural white, the glass-filled top-entry header wafer as glass-filled PA 66, and the SMT wafer as PA 6T. KONNRA documents the KR2501 material as PA9T / LCP / UL94 — high-temperature nylons, not PA 6. This is a materials substitution rather than a dimensional one, and it shows up in reflow exposure, dimensional stability and cost. If your qualification or your soldering profile assumes the JST polymer, confirm the equivalent property data.

1. Circuit count — the 20-position and 1-position gap. JST’s XH housing range includes XHP-20, and the top-entry header range includes B20B-XH-A at 20 circuits. JST also lists a 1-circuit housing, XHP-1. The KONNRA KR2501 is documented from 2 to 16 circuits. If your design uses 20 positions — or a single-position plug — check availability rather than assuming the series stops where the cross-reference does.

1. Three terminals on the JST side, one documented on the KONNRA side. The KR2501 is documented with a single crimp terminal. JST splits the XH into a normal 001, a fine-wire 002, and a low-insertion-force 001N, with different conductor and insulation windows for each. If your harness runs at the ends of the range — AWG #30 conductor, or a low-insertion-force requirement — confirm the accepted conductor and insulation dimensions in writing.

JST XH / KR2501 Component and Configuration Options

The KR2501 is specified as six separately orderable components, each with its own product drawing — which is what lets the same series serve both through-hole and SMT assemblies.

DIP straight wafer (180° / top entry, through-hole)

2.5mm pitch through-hole header, single row 2–16 circuits, 3A, 250V. The through-hole equivalent of JST’s top-entry B…B-XH-A header, and the configuration that carries the friction-lock retention load through the shrouded box.

Figure 2 — KR2501 DIP straight (180°) wafer, through-hole top entry

➡️ KR2501 DIP Straight Wafer

SMT straight wafer (180° / top entry, surface mount)

2.5mm pitch SMT header, single row 2–16 circuits, 3A, 250V. The surface-mount route for the same footprint decision.

Figure 3 — KR2501 SMT straight (180°) wafer, surface-mount top entry

➡️ KR2501 SMT Straight Wafer

DIP right-angle wafer (90° / side entry, through-hole)

2.5mm pitch through-hole side-entry header, single row 2–16 circuits, 3A, 250V. Choose this when the cable leaves the board horizontally and you have depth rather than height available.

Figure 4 — KR2501 DIP right-angle (90°) wafer, through-hole side entry

➡️ KR2501 DIP Right Angle Wafer

SMT right-angle wafer (90° / side entry, surface mount)

2.5mm pitch SMT side-entry header, single row 2–16 circuits, 3A, 250V.

Figure 5 — KR2501 SMT right-angle (90°) wafer, surface-mount side entry

➡️ KR2501 SMT Right Angle Wafer

Housing

2.5mm pitch wire housing with friction lock, single row 2–16 circuits. Material is PA9T / LCP rated UL94.

Figure 6 — KR2501 2.5mm pitch wire housing with friction lock

➡️ KR2501 Housing

Terminal

2.5mm pitch crimp contact, 3A max, 250V, contact resistance 20mΩ max, insulation resistance 1,000MΩ min, withstanding voltage 250V AC / minute, insulation O.D. 1.2–1.8mm, tin over nickel plating. Before you specify this terminal, check which wire range you actually need. JST splits its XH terminals into a normal 001, a fine-wire 002 and a low-insertion-force 001N, with conductor and insulation windows that only partly overlap — see the terminal section above — and the KR2501 terminal is documented with a single insulation range of 1.2–1.8mm. If your harness uses wire at the ends of the range, confirm the accepted conductor and insulation dimensions in writing.

Figure 7 — KR2501 crimp terminal for 2.5mm pitch wire-to-board connections

➡️ KR2501 Terminal

Full series documentation

• KR2501 series engineering drawing (PDF)
• KR2501 product specification (PDF)
• KR2501 package specification (PDF)

➡️ Request drawings for your specific circuit count and mounting type

Through-Hole or SMT: How to Choose

The ZH and SH families sit at opposite ends of this question — the ZH offers both mounting technologies across its range, and the SH is SMT-only. The XH is a third case: it offers both, but JST catalogues the SMT type only in 3, 4 and 6 circuits (S3B-XH-SM4-TB, S4B-XH-SM4-TB, S6B-XH-SM4-TB), while the through-hole headers run from 2 to 16 and 20 circuits. Above six positions at 2.5mm, the XH is a through-hole connector.

	Through-hole (DIP)	Surface mount (SMT)
KR2501 components	DIP straight 180°, DIP right-angle 90°	SMT straight 180°, SMT right-angle 90°
JST XH equivalents	B…B-XH-A (top), S…B-XH-A (side), plus -1 for the 7.6mm end-face-to-post version, -AM for the boss version, -2 for glass-filled nylon	S3B-XH-SM4-TB, S4B-XH-SM4-TB, S6B-XH-SM4-TB
JST circuit range	2 – 16 and 20	3, 4 and 6 only
Mechanical strength	Higher — the pins pass through the board and are soldered, and the friction lock loads the shroud	Lower — retention is by the solder tab and joint only
Board real estate	Needs a hole pattern and clearance on the far side	Pads a solder tab only; frees the far side for other routing
Assembly	Separate wave/selective solder operation	Placed and reflowed with the rest of the SMT line
Applicable board thickness	JST specifies 1.6mm	Not applicable
Best for	Cables that are plugged and unplugged, or pulled on — which at 3A is most power wiring	High-volume assembly where every insertion operation costs money

The practical rule. Choose through-hole when the connector will see repeated mating cycles or cable pull — at this pitch and current rating, the friction lock is doing real work and the pins carry the load. Choose SMT when assembly cost and board real estate matter more than mechanical retention, the circuit count is six or fewer, and the cable is likely to be routed and left in place. Check the far side of the board. A through-hole header needs clearance behind the PCB. In a stacked design, that clearance may not exist — which is the most common reason an XH design ends up SMT despite a preference for through-hole. Note on the side-entry dimension. JST offers the side-entry header in two sizes: a standard version with 9.2mm from the end face of the mating part to the post, and a 7.6mm version for 2 to 15 circuits, ordered by adding -1 to the model number. The 1.6mm difference decides whether the connector clears an adjacent component or an enclosure wall. If you are replacing a competitor’s side-entry header, check this dimension before you assume the footprint matches. Note on the boss and glass-filled types. JST splits its through-hole XH headers three ways: the standard B…B-XH-A, a with-boss version (-AM) that locates the header mechanically during placement and assembly, and a glass-filled nylon version (-2) for additional dimensional stability. KONNRA documents the KR2501 DIP wafers as straight 180° and right-angle 90°. If your design specifically relies on boss geometry or the glass-filled wafer, confirm that detail against the KR2501 drawing rather than assuming it.

JST XH 2.5 vs SH 1.0 vs GH 1.25 vs ZH 1.5 vs PH 2.0

These five JST families cover almost every compact wire-to-board design, and they are constantly confused because they share a design language. They are not interchangeable at any level.

Feature	JST SH 1.0	JST GH 1.25	JST ZH 1.5	JST PH 2.0	JST XH 2.5
Pitch	1.0mm	1.25mm	1.5mm	2.0mm	2.5mm
Current rating	1A (AWG #28)	1A (AWG #26)	1A (AWG #26)	2A (AWG #24)	3A (AWG #22)
Voltage rating	50V AC/DC	50V AC/DC	50V AC/DC	100V AC/DC	250V AC/DC
Operating temperature	−25 to +85°C	−25 to +85°C	−25 to +85°C	−40 to +105°C	−25 to +85°C
Wire size	AWG #32–#28	AWG #30–#26	AWG #32–#26 (by terminal)	AWG #32–#24	AWG #30–#22 (by terminal)
Mounting	SMT only	SMT only	Through-hole and SMT	Through-hole and SMT	Through-hole (limited SMT)
Typical use	Micro FPV, wearables, compact IoT	Pixhawk / ArduPilot standard	Micro servos, compact sensors, Raspberry Pi accessories	LiPo batteries, Arduino-class sensors	3D printers, RC receivers, power wiring
KONNRA equivalent	KR1000	KR1259	KR1501	KR2004 / KR2001	KR2501

All JST figures in this table are taken from JST’s own series documentation for SH, GH, ZH, PH and XH. How to choose.

• 1A or less, and board height is the constraint → SH 1.0 / KR1000. Smallest of the five.
• 1A or less, and you need the Pixhawk ecosystem standard → GH 1.25 / KR1259.
• 1A, and you want a mechanically locked connector with a compact-but-handleable pitch → ZH 1.5 / KR1501.
• Up to 2A, common in hobby, battery and Arduino-class wiring → PH 2.0 / KR2004.
• Up to 3A at 250V, and the cable is a power lead rather than a signal run → XH 2.5 / KR2501.

Two things this table makes clear. First, both current and voltage step up with pitch — 1A/50V across the three compact families, then 2A/100V for PH, then 3A/250V for XH. The jump from ZH to XH is the largest single step in the range: three times the current and five times the voltage. If your design crosses 50V or needs more than 2A, ZH is not the answer whatever the space constraint says. Second, the XH’s temperature range is not the widest despite it being the largest part — JST documents the PH at −40 to +105°C, while the XH is specified at −25 to +85°C.

The 2.5mm pitch class is the most crowded one JST makes

The XH is not the only JST family at 2.5mm. JST documents the EH series at the same 2.5mm pitch with the same headline ratings — 3A AC/DC (AWG #22) and 250V AC/DC — and KONNRA’s 2.5mm range also cross-references the JST XA series alongside the XH. They are different series with different housings, headers and terminals. Two connectors at the same pitch and the same current rating will not necessarily mate, and they will rarely share a footprint. At 2.5mm the pitch tells you almost nothing about which connector you are holding — cross-reference on the part number, not on the pitch or the appearance.

Is the XH 2.5mm or 2.54mm?

JST documents the XH at a 2.5mm pitch, and dimensions the through-hole layout at 2.5 ±0.05mm between contact centres. The “2.54mm” label is widespread in the trade because 2.54mm is exactly 0.1 inch — the pitch of the classic 0.1-inch pin header — and XH connectors are routinely used on the same boards as those headers. They are not the same pitch, and the difference compounds. Across a 16-circuit connector the gap between a 2.5mm and a 2.54mm contact field accumulates to 0.6mm. That is enough to matter on a hole pattern. If a drawing, a bill of materials or a distributor listing says 2.54mm for an XH-family part, confirm which connector it actually calls for before you quote tooling.

Circuit Count Range and PCB Layout Considerations

JST’s XH housing table runs from XHP-1 through XHP-16, plus XHP-20. The KONNRA KR2501 is documented from 2 to 16 circuits. The table below gives JST’s own housing “A” and header “B” dimensions for common configurations at the 2.5mm pitch.

Circuits	Housing A dimension	Header B dimension
2	2.5mm	7.4mm
3	5.0mm	9.9mm
4	7.5mm	12.4mm
5	10.0mm	14.9mm
6	12.5mm	17.4mm
7	15.0mm	19.9mm
8	17.5mm	22.4mm
10	22.5mm	27.4mm
12	27.5mm	32.4mm
13	30.0mm	34.9mm
16	37.5mm	42.4mm
20	47.5mm	52.4mm

How to read this table. The housing “A” dimension is the distance across the contact field: A = (N − 1) × 2.5mm, where N is the circuit count. This is a useful cross-check on any drawing — JST lists XHP-4 at 7.5mm and XHP-16 at 37.5mm, both of which the formula reproduces. The header “B” dimension is the overall header length and is not the same number, because the shroud adds material at both ends. Overall dimensions, the hole or pad pattern, and stencil recommendations must come from the KR2501 drawings linked above. Board design notes:

• Confirm DIP or SMT, and straight 180° or right-angle 90°, before quoting. That is four possible footprints from one series — and above six circuits, SMT is not catalogued by JST at all.
• Confirm the side-entry dimension: standard is 9.2mm from the mating face to the post, with a 7.6mm version available for 2 to 15 circuits by adding -1 to the part number.
• A through-hole header needs clearance on the far side of the board. Check it before designing around DIP.
• JST specifies the XH for 1.6mm PC board thickness. If your stack-up differs, confirm the post length and hole dimensions against the drawing.
• Tie the accepted wire insulation diameter to the connector drawing. The JST XH terminals accept 0.9–1.9mm depending on which terminal you select, and KONNRA documents the KR2501 at 1.2–1.8mm.
• Select the terminal before the housing. Wire size drives the terminal choice, and the terminal choice drives the accepted insulation diameter.
• Specify gold plating explicitly if you need it. Standard JST XH contacts are phosphor bronze, tin-plated with reflow treatment, with gold available on request; KONNRA documents tin over nickel on the KR2501.
• Remember the polarization. The XH housing and header are keyed, so the connector seats in one orientation only — but so are the ZH, PH and EH housings, in different ways. Photograph the assembly rather than relying on memory.

The KONNRA 2.5mm Pitch Connector Family

Series	Cross-referenced to	Circuits	Current	Voltage	Rows	Category
KR2501	JST XH 2.5	2 – 16	3A	250V	1	Wire-to-Board
KR2500	Molex Mini-SPOX 2.50	2 – 16	3A	250V	1	Wire-to-Board
KR2502	Yeonho YH 2.5	2 – 20	3A	250V	1	Wire-to-Board
KR2504	JST EH 2.5	2 – 16	3A	250V	1	Wire-to-Board
KR2507	JST SM 2.5	2 – 16	3A	250V	1	Wire-to-Wire
KR2508	JST SCN 2.5	2 – 15	3A	250V	1	Board-In
KR2511	XHQ 2.5	2 – 16	3A	250V	1	Wire-to-Board
KR2516	JST XA 2.5	2 – 15	3A	250V	1	Wire-to-Board
KR2556	MX23A (automotive)	18 / 26 / 34	3A	1,000V	2	Automotive Connectors

Decision rule: compact 3A at 250V with a friction lock and a shrouded header → KR2501. Need the EH pattern or a different latching geometry in the same pitch class → KR2504. Need wire-to-wire rather than wire-to-board → KR2507. Need a board-in termination → KR2508. Need an XA-pattern wire-to-board → KR2516. ➡️ Explore the full 2.5mm pitch range · Wire-to-board connector catalogue

Applications and Cable Assembly Options

Application	Why the KR2501 fits
3D printer mainboards and hot-end wiring	2.5mm pitch tolerates repeated mating during maintenance, and 3A covers heater and fan loads
RC and hobby battery wiring	XH-pattern connectors are the de facto standard on LiPo packs and balance leads; 3A/250V covers typical pack wiring
Home appliances	Control board to module wiring at mains-derived low voltage, with a friction lock that survives vibration
Industrial control and network equipment	Board-to-module signal and low-power wiring with a fully shrouded header
Power tools and motor drives	Vibration resistance from the box-shaped shroud and the friction lock
Automotive modules	Supported by KONNRA’s IATF16949 automotive quality system and automotive-grade series
Medical devices	Supported by KONNRA’s ISO13485 medical device quality system
Lighting and LED modules	Multi-position power distribution at a pitch that is still hand-serviceable

Cable assembly options

KONNRA builds cable assemblies on the KR2501 system in the standard harness configurations:

Cable type	Description	Typical use
Single-headed	Housing on one end, bare wire leads on the other	Pigtail to a header, panel wiring
Same-side-head	Housing on both ends, same orientation	Board-to-board extension, same-direction routing
Reverse-side-head	Housing on both ends, reversed orientation	Board-to-board extension, reversed routing
Adapter cables	KR2501 on one end, another series on the other (for example XH-to-PH, XH-to-DuPont or XH-to-JST-VH)	Interfacing a 2.5mm device to a 2.0mm, 2.54mm or 3.96mm board

Cable assemblies are produced in KONNRA’s wiring harness division, which accounts for 40% of company sales and operates its own injection moulding and assembly workshops. Adapter and transition cables are a common requirement in the XH world — connecting an XH-terminated battery or appliance module to a 2.54mm header on a controller board is the classic case — and are built to order. Connector lead time is typically 2–3 weeks; wiring harness lead time is typically 3–4 weeks. ➡️ Explore KONNRA wiring harness capabilities

Sourcing the JST XH 2.5: What Procurement Teams Ask

Engineering decides that a connector will work. Procurement decides whether the supply chain around it is safe. “Can you be a second source without changing our design?” That is what a documented cross-reference is for. The KR2501 is specified against the JST XH at component level — housing, header, and terminal — with matching pitch, friction lock and shrouded box header. We confirm equivalence against your specific part number, because circuit count, entry direction and mounting type change the answer. “What are your lead times?” Connector production lead time is typically 2–3 weeks. Wiring harness lead time is typically 3–4 weeks. Key materials are prestocked to shorten cycles. “How long for samples?” Complete connector set samples can be delivered within 45 days. Where you need to validate crimp quality or a cable assembly before committing, sample harnesses can be supplied from the same process used in production. “What qualifications do you hold?” ISO9001, ISO14001, IATF16949, ISO45001:2018, ISO13485, IPC620, and UL product and operational safety certifications. Automotive-grade series additionally hold LV214 and US CAR-2. “How do we know the parts match your documentation?” A CNAS-accredited laboratory with 45+ sets of precision testing instruments, with dimensional and electrical verification data available on request. 95% of production processes carry full-line intelligent visual CCD inspection; automotive series receive 100% CCD inspection. “Are you a manufacturer or a trader?” A manufacturer. Dongguan Konnra Electronics Co., Ltd., founded 2004, with in-house mould design, injection moulding, stamping, assembly, and inspection — which is why the connector and the cable assembly can come from one quality system. “What volumes can you support?” KONNRA reported 2025 sales of RMB 310 million, with connectors at 60% and wiring harnesses at 40% of the product mix, across four production bases with automation coverage exceeding 95%. “Who else buys from you?” KONNRA states that it serves global cooperative clients including BYD, Volkswagen, and DJI. ➡️ Request the vendor qualification pack — certificates, test capability summary, product drawings, and a sample plan in one enquiry.

How to Get a Cross-Reference Check on Your Part Number

Most XH sourcing enquiries stall on the same thing: the buyer is not sure what information the supplier needs, so the enquiry never gets sent. Here is the complete list. Send us:

1. The original JST part number, if you have it — for example XHP-4, B4B-XH-A, S4B-XH-SM4-TB, or SXH-001T-P0.6 / SXH-002T-P0.6 / SXH-001T-P0.6N
2. Circuit count and row configuration
3. Mounting type and entry direction — DIP or SMT, top entry (straight) or side entry (right-angle). If side entry, tell us whether you need the 9.2mm or the 7.6mm end-face-to-post dimension
4. Wire specification — AWG size and insulation outside diameter. At 2.5mm the insulation diameter decides the terminal as much as the conductor does
5. Application and annual volume, so configuration, tooling and packaging can be matched to your programme
6. A drawing or photo, if the part number is unreadable or the design has been reverse-engineered. A photo next to a ruler identifies pitch, but at 2.5mm it will not separate XH from EH or XA — send the part number if you have it
7. Any qualification requirements — automotive, medical, or specific test standards

When you send a terminal part number, we will confirm the wire and insulation range against JST’s own documentation. The three XH terminals overlap on AWG #26–#28 but do not share the same insulation window, so a harness drawing that names a terminal and an insulation diameter that do not go together is a common failure — we will flag it before it becomes a failed build. What you get back: a mapped KONNRA part number with the relevant product and engineering drawings, a specification comparison against your original part, and a sample and quote plan.

Engineer’s Pre-Release Checklist

Run this before you release a drawing for a 2.5mm pitch connector.

• Pitch confirmed by measurement or part number — not by appearance. 2.5mm is not 2.54mm, and XH, EH and XA all sit at 2.5mm without sharing a footprint.
• Series confirmed — XH, EH or XA. At this pitch the part number is the only reliable identifier.
• Terminal selected by wire size — then check the insulation diameter against that specific terminal’s window, not the series range.
• Low-insertion-force not specified by default. SXH-001T-P0.6N is documented by JST as less resistant to vibration. Use it only where mating effort is the binding constraint.
• Mounting type decided — DIP or SMT — and the circuit count is inside the range that mounting type is catalogued for. Above six circuits, JST lists no SMT XH.
• Side-entry dimension confirmed — 9.2mm standard, or 7.6mm with the -1 suffix for 2 to 15 circuits.
• Through-hole clearance checked on the far side of the board, and board thickness inside the 1.6mm JST specifies.
• Voltage and current checked against the rating. XH is a 3A/250V family; above that, move up the pitch range.
• Withstanding voltage confirmed — JST documents 1,000 VAC/minute, KONNRA documents 250V AC/minute. Verify which figure your specification requires.
• Plating stated explicitly if gold is required — tin is the JST XH standard finish.
• Mated height checked against the enclosure, including cable bend radius behind the housing.

➡️ Send us your drawing. We will review it against the KR2501 specification and come back with any mismatch we find — before you commit tooling. Submit a drawing for review

Why Source JST XH 2.5 Connectors from 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 depth. A vertically integrated process covering precision mould design and manufacturing, automation design, precision injection moulding, stamping, assembly, and CCD visual inspection. Automation coverage exceeds 95% across production lines. Testing and validation. A CNAS-accredited laboratory with 45+ sets of precision testing instruments, and CAE analysis — contact nonlinear analysis, material nonlinear analysis, motion simulation, thermal field analysis, and high-frequency analysis — performed in Ansys 2022 R1. Verification data is available on request. Inspection coverage. Full-line intelligent visual CCD inspection covers 95% of production processes, using Mitsubishi and Panasonic PLC control systems with FA25–35mm optical lenses and 5-megapixel cameras. Automotive connector series receive 100% CCD visual inspection. 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. Capacity and delivery. Production bases in Dongguan Wangniudun (30,000 m², 350+ employees), Dongguan Changan (10,000 m², 150+ employees), and Hunan Daoxian (2,600 m², 100+ employees), with regional offices in Beijing, Chongqing, Hunan, Shanghai, and Kunshan. Key materials are prestocked, and complete connector set samples can be delivered within 45 days. KONNRA reported 2025 sales of RMB 310 million, with connectors at 60% and wiring harnesses at 40% of the product mix, and has served global cooperative clients including BYD, Volkswagen, and DJI. Custom and joint R&D. Where a standard 2.5mm part does not fit — an unusual circuit count, a specific mounting height, a right-angle configuration, or a material requirement — KONNRA supports customer joint R&D customisation.

Frequently Asked Questions

What is a JST XH connector?

The JST XH is a 2.5mm pitch, single-row, wire-to-board crimp connector with a friction lock and a box-shaped shrouded header. It is rated 3A AC/DC at 250V AC/DC, mates at a 9.8mm mounting height, and accepts AWG #30 to #22 wire with insulation O.D. from φ0.9mm to φ1.9mm depending on terminal. JST developed it from its NH series, and documents the header as interchangeable with the NR and NRD insulation-displacement connectors and the JQ board-to-board connector.

What is the KONNRA equivalent of the JST XH 2.5?

The KONNRA KR2501 series — a 2.5mm pitch XH wire-to-board connector covering 2–16 circuits at 3A and 250V, offered as DIP straight 180°, DIP right-angle 90°, SMT straight 180° and SMT right-angle 90° wafers, plus a housing and a crimp terminal.

Which SXH terminal goes with which wire size?

Three terminals, with ranges that only partly overlap. SXH-001T-P0.6 is the default: AWG #28 to #22 (0.08–0.33mm²), insulation 0.9–1.9mm. SXH-002T-P0.6 is the fine-wire part: AWG #30 to #26 (0.05–0.13mm²), insulation 0.9–1.3mm. SXH-001T-P0.6N is the low-insertion-force contact: AWG #26 to #22 (0.13–0.33mm²), insulation 1.3–1.9mm, and JST states it is less resistant to vibration than the standard contact. The series-level applicable wire range is AWG #30 to #22 — the union of all three.

Is the JST XH 2.5mm or 2.54mm?

2.5mm. JST dimensions the through-hole layout at 2.5 ±0.05mm between contact centres. The 2.54mm label is common in the trade because 2.54mm is exactly 0.1 inch, but the two are not the same pitch — across 16 circuits the difference accumulates to 0.6mm.

What is the current and voltage rating of the JST XH?

3A AC/DC per contact with AWG #22 wire, at 250V AC/DC. The KONNRA KR2501 is documented at the same 3A and 250V. Note that the current rating is per contact and is specified with AWG #22 — a thinner conductor derates the connection, and the SXH-002T-P0.6 terminal only accepts up to AWG #26.

What wire gauge does the JST XH use?

AWG #30 to #22 (0.05 to 0.33mm²), with an insulation outside diameter from φ0.9mm to φ1.9mm, depending on which of the three terminals you select. AWG #22 is the gauge at which JST rates the full 3A; AWG #30 is only accepted by the SXH-002T-P0.6 fine-wire terminal.

What is the insulation resistance and withstanding voltage of the JST XH?

Insulation resistance 1,000MΩ minimum. Withstanding voltage is 1,000 VAC applied for one minute with no breakdown or flashover in JST’s documentation. KONNRA documents the KR2501 at the same 1,000MΩ insulation resistance but at 250V AC per minute for withstanding voltage — a four-fold difference that should be resolved against your own specification before qualification.

What is the difference between JST XH and JST PH?

Pitch, current and voltage. XH is 2.5mm, 3A, 250V; PH is 2.0mm, 2A, 100V. JST also documents the PH at a wider operating temperature range (−40 to +105°C) than the XH’s −25 to +85°C. They do not mate and do not share footprints. The KONNRA equivalents are KR2501 (XH) and KR2004 (PH).

What is the difference between JST XH and JST EH?

Both are 2.5mm pitch families, and JST documents both at 3A AC/DC (AWG #22) and 250V AC/DC. They are nevertheless different series with different housings, headers and terminals — the pitch and the headline ratings will not tell you which one you are holding. Cross-reference on the part number. The KONNRA equivalent for XH is KR2501; for EH it is KR2504.

Does the JST XH have an SMT version?

Yes, but only in 3, 4 and 6 circuits — S3B-XH-SM4-TB, S4B-XH-SM4-TB and S6B-XH-SM4-TB, side entry with a solder tab, supplied on embossed tape. Above six circuits JST catalogs the XH as a through-hole connector only. KONNRA documents KR2501 SMT wafers as straight 180° and right-angle 90° across the 2–16 circuit range.

How many circuits does the JST XH come in?

JST’s XH housing table runs from XHP-1 through XHP-16, plus XHP-20. Headers are catalogued from 2 to 16 circuits, plus 20 for top entry. The KONNRA KR2501 is documented from 2 to 16 circuits — if you need 20 positions, check availability rather than assuming the series ends where the cross-reference does.

What is the mounting height of the JST XH?

9.8mm. JST describes the connector as very small at that height for a 2.5mm pitch part. Both JST and KONNRA document the same 9.8mm figure, so enclosure clearance does not change when you cross-reference.

Can the JST XH header be used with IDC termination?

Yes — JST documents the XH header as interchangeable with the NR and NRD insulation-displacement connectors, and also with the JQ board-to-board connector. So the same PCB footprint can carry crimp, IDC or board-to-board termination. KONNRA does not document an NR, NRD or JQ equivalent for the KR2501, so confirm this specifically if your design depends on it.

How do I identify which JST connector I actually have?

Measure the pitch — the centre-to-centre distance between adjacent contacts. 1.0mm is SH, 1.25mm is GH, 1.5mm is ZH, 2.0mm is PH, 2.5mm is XH. Then check the housing width: the XH housing “A” dimension is (N − 1) × 2.5mm, so a 4-circuit XH housing measures 7.5mm across the contact field. Because EH and XA also sit at 2.5mm, the housing profile and the part number are the deciding evidence. If you are still unsure, photograph the connector next to a ruler and send it to us.

How long does it take to get samples?

KONNRA can deliver complete connector set samples within 45 days. Connector production lead time is typically 2–3 weeks and wiring harness lead time typically 3–4 weeks.

Start Your Cross-Reference Check

KONNRA supplies the KR2501 series as individual components or as complete pre-crimped cable assemblies, in DIP and SMT configurations, with customisation available for application-specific requirements.

• Request a quote — KR2501 pricing, MOQ, and configuration options for your circuit count and mounting type
• Request a sample — complete connector set samples within 45 days
• Request cross-reference verification — confirm KR2501-to-JST XH 2.5 equivalence against your specific part number, including terminal wire and insulation ranges
• Request drawings — series engineering drawing, product specification, and package specification
• Request a vendor qualification pack — certificates, test capability summary, and quality documentation
• Request adapter and transition cable assemblies — XH to PH, XH to DuPont, XH to JST VH, or other combinations
• Submit a drawing for review — we will flag any specification mismatch before you commit tooling

Contact KONNRA Electronics

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

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Sources and method. JST XH figures are taken from JST’s published XH series documentation: pitch (2.5mm), mounting height (9.8mm), current rating (3A AC/DC with AWG #22), voltage rating (250V AC/DC), temperature range (−25°C to +85°C including temperature rise under load), contact resistance (10mΩ max initial, 20mΩ max after environmental tests), insulation resistance (1,000MΩ min.), withstanding voltage (1,000 VAC for one minute, no breakdown or flashover), applicable wire (AWG #30 to #22, 0.05–0.33mm²), insulation O.D. (φ0.9–1.9mm), applicable PC board thickness (1.6mm), housing part numbers and dimensions (XHP-1 through XHP-16 and XHP-20), through-hole header part numbers (top entry B…B-XH-A and B20B-XH-A; side entry S…B-XH-A with the -1 7.6mm variant; the with-boss -AM series; the glass-filled -2 series), SMT header part numbers (S3B-, S4B- and S6B-XH-SM4-TB), radial-tape header part numbers (TV4 and 2-TV4), terminal part numbers with wire and insulation ranges (SXH-001T-P0.6: AWG #28–#22, 0.08–0.33mm², insulation 0.9–1.9mm; SXH-002T-P0.6: AWG #30–#26, 0.05–0.13mm², insulation 0.9–1.3mm; SXH-001T-P0.6N: AWG #26–#22, 0.13–0.33mm², insulation 1.3–1.9mm, low-insertion-force type), contact material and finish (phosphor bronze, tin-plated with reflow treatment; gold-plated and brass contacts on request), housing and wafer materials, the friction lock, the 9.8mm assembled height, the NH-series development basis, the NR / NRD / JQ interchangeability, the applicable standards, and RoHS2 status. The JST SH, GH, ZH and PH figures in the cross-series comparison table are likewise taken from JST’s own series documentation for those families. The JST EH figures quoted in the 2.5mm pitch discussion (2.5mm pitch, 3A AC/DC with AWG #22, 250V AC/DC) are taken from JST’s published EH series documentation. KONNRA KR2501 specifications, component part numbers and the 2.5mm pitch family table are taken from KONNRA’s published product and component documentation. Where the two sources disagree, or where a widely-circulated third-party figure differs from the manufacturer’s, the difference is stated in this guide rather than smoothed over. Always confirm final dimensional and electrical requirements against the current manufacturer drawing for your specific part number.

https://konnra.com/jst-xh-2-5-connector-complete-guide/
Dongguan Konnra Electronics Co., Ltd