Electronics — Order spec

Order spec

Reference

Order-ready cable build list for a custom harness vendor.

Every TBD from the wire harness page is filled in with a stated guess. Lengths are kept deliberately long; if a cable comes back a little wrong we iterate. IDs match the wire schedule.

Guesses inside. Gauges, connector part numbers, and the chute stepper length are engineering guesses, not measurements. They are conservative and safe to order against. Verify list in section 7.

1 Global spec

Wire: UL1007 stranded, 300V, tinned copper
Gauges: 18 AWG (PSU box internals) · 22 AWG (all barrel-plug 24V runs, LED feeds, limit switch) · 24 AWG (stepper cables, set by the JST-PH contact limit)
Colors: Red = +24V, black = GND on all 2-conductor power cables. Steppers: see pin maps, section 3.
Barrel jacks: 5.5 mm OD × 2.1 mm ID, center-positive, rated ≥5 A
Length tolerance: ±10 mm (±25 mm fine on anything ≥36 in)
Bare ends: Strip 5 mm, tin
Labeling: Each cable labeled with its ID (W1, S1…) on a flag label near end A
Order quantity: 2 full sets recommended, because lengths are guesses and spares are cheap

2 Cable build list

One row = one buildable cable SKU. End A is the PSU/board side. "Bare" ends are for parts the vendor cannot terminate (section 4).

ID	Qty	Gauge	Length	Cond.	End A	End B	Notes
PSU-J	3	18 AWG	4 in	2	2× insulated spade/fork terminal, M3.5, 8 mm wide max	Panel-mount female DC jack 5.5×2.1	Lives inside the PSU box. Usually comes already attached to the jack, so buy the jacks with leads
W1	1	18 AWG	36 in	2	Male DC plug 5.5×2.1	JST VHR-2 + SVH-21T-P1.1 contacts	Board 24V in. Pin 1 = +24V verify silkscreen
W2	1	22 AWG	12 in	2	Male DC plug 5.5×2.1	Male DC plug 5.5×2.1	USB hub. Double-male, center-positive both ends verify hub jack size
W3	1	22 AWG	6 in	2	Male DC plug 5.5×2.1	Bare, tinned	Splice to USB-C buck input leads
L1-L3	3	22 AWG	36 in	2	Dupont 1x2 female (2.54 mm)	Female inline DC jack 5.5×2.1	LED feed from board to unplug point
L1p, L2p	2	22 AWG	6 in	2	Male DC plug 5.5×2.1	Bare, tinned	Solder to COB board pads
L3p	1	22 AWG	6 in	2	Male DC plug 5.5×2.1	Bare, tinned	Into a solderless clamp-on strip connector (6000K strip)
LIM	1	22 AWG	24 in	2	Dupont 1x3 female (2.54 mm), position 3 empty	2× insulated quick-connect receptacle, #187	Pushes onto the switch tabs, no soldering. Empty third position keys the board end
S1-S4	4	24 AWG	1 m	4	JST PHR-4 + SPH-002T contacts	JST PHR-6 + SPH-002T contacts	Crossover cable, pin map 3.2. Into the motor's own 6-pin socket. 4-wire bundle in PVC sleeving
CH	1	24 AWG	40 in guess	4	JST PHR-4 + SPH-002T contacts	Bare, tinned, 4 leads labeled 1-4	Splice to chute stepper flying leads, pin map 3.3

Steppers move to JST-PH. This spec adopts the recommended change: stepper cables plug the board's JST-PH 4-pin jacks (J23, J27, J31, J35, J39) instead of dupont on the parallel pin headers. PH contacts accept 24-28 AWG, hence 24 AWG on S1-S4 and CH. The mains inlet wiring (18 AWG, 3-cond.) comes pre-made on the 3Dman inlet switch and is not part of this order. The 16-pin IDC ribbon is an off-the-shelf uxcell part: buy, don't build.

3 Pin maps

3.1 2-conductor power (PSU-J, W1-W3, L1-L3, pigtails)

Barrel jacks and plugs are 5.5 × 2.1 mm everywhere, confirmed against the Waveshare hub (part DC-044 on their wiki). 5.5 × 2.5 also exists and does not mate, so specify 2.1 on every line. Center/tip = +24V (red), sleeve = GND (black). W1 board end: VH pin 1 = +24V, pin 2 = GND, verify against board silkscreen before ordering. LED feed dupont: pin 1 = +24V, pin 2 = GND, same caveat.

3.2 Channel stepper cable S1-S4 (crossover)

The motor end is a 6-position housing with only 4 positions populated, so the four board positions land on motor 1, 4, 3 and 6. Motor positions 2 and 5 stay empty. The nets match end to end; the positions do not.

Board PHR-4 pos.	Net	Motor PHR-6 pos.	Color
1	A2	1	blue
2	A1	4	green
3	B1	3	red
4	B2	6	black
—	—	2, 5	unpopulated

For the vendor, explicitly: this is NOT a straight-through cable, and the two ends have a different number of positions. Board 1→motor 1, board 2→motor 4, board 3→motor 3, board 4→motor 6. Motor positions 2 and 5 are left empty.

3.3 Chute stepper cable CH (straight, bare end)

Board PH pin	Net	Coil	Color
1	A2	A	black
2	A1	A	green
3	B1	B	red
4	B2	B	blue

Straight-through, coil pairs = 1-2 and 3-4. Identify the motor's coil pairs with a multimeter (a coil reads a few ohms, across coils reads open) before splicing. Swapping within a coil only flips direction.

3.4 Drawings (WireViz)

Rendered harness drawings, BOMs, downloads, and the full supplier package live on the WireViz page. Every guessed value is marked GUESS in the drawings themselves.

4 Ends the vendor can't terminate

Some parts come with their own fixed leads or solder pads, so the harness can't fully land on them. Those cables are ordered with one end bare and tinned, and joined on the machine:

24V to 5V USB-C buck (W3): converter has fixed input leads, so splice.
Chute stepper (CH): flying leads out of the motor, so splice.
COB boards (L1p, L2p): solder pads, so solder direct.
LED strip (L3p): a solderless clamp-on connector bites onto the cut strip, so no soldering. Pick the variant with IDC crimp points on both sides and it takes the pigtail wire too.

Splice spec: solder splice plus adhesive-lined heat shrink, one sleeve per conductor plus an overall sleeve. No twist-and-tape, no inline lever nuts.

5 Connector BOM

Genuine JST part numbers given where they exist. Chinese-clone equivalents of all of these are fine for a vendor quote.

Connector	Housing	Contacts	Used on
JST VH 2-pin	VHR-2	SVH-21T-P1.1 (16-22 AWG)	W1 board end
JST PH 4-pin	PHR-4	SPH-002T-P0.5S (24-28 AWG)	S1-S4, CH board ends
JST PH 6-pin	PHR-6	SPH-002T-P0.5S (24-28 AWG)	S1-S4 motor end, into the NEMA 17 socket
Dupont 1x2 female, 2.54 mm	generic dupont housing + female crimps (any vendor stocks these)		L1-L3 board ends
Dupont 1x3 female, 2.54 mm	generic housing + female crimps, only 2 positions populated		LIM board end (the empty position keys it)
Quick-connect receptacle, #187	fully insulated female, 4.75 × 0.5 mm (.187 × .020 in) tab, 22 AWG		LIM switch end (Omron V-155-1C25)
DC barrel male 5.5×2.1	moulded plug w/ lead, or field-installable		W1-W3, L pigtails
DC barrel female inline 5.5×2.1	moulded inline jack		L1-L3 unplug points
DC barrel female panel-mount 5.5×2.1	panel-mount jack, ≥5 A		PSU box outputs J1-J3
Spade/fork terminal, insulated	18 AWG, M3.5 stud, 8 mm wide max, must fit the LRS-350-24 output screws		PSU-J

6 How to order this

Custom harness vendor (Alibaba "custom cable assembly", or a US quick-turn shop): send them sections 1-3 and 5 as the drawing. Expect MOQ 50-100 pcs per line item from China; small US shops and some AliExpress custom-cable storefronts will do 5-10.
Low volume alternative: buy pre-crimped PH / XH / dupont leads plus housings and assemble. The only labor a vendor saves is crimping.
The rationale for every guess in this spec: steppers draw ≤1.5 A/phase (24 AWG ok at these lengths), no single barrel-plug load exceeds ~3 A (22 AWG ok), PSU box pigtails carry worst-case single-load current (18 AWG).
The 24V distribution feeds three loads: the board, the USB hub, and the Orange Pi buck. The cooling fans are not on it, they run off the Pi or the board.

7 Guesses to verify before sending

Board 24V input polarity: which pin is +24V. The connector itself is settled as VH (VHR-2, 18 AWG).
Chute stepper cable: 40 in copied from the channel steppers, and it is not covered by Jon's drawing at all.
LED drop count: 3 feeds + 3 pigtails, per the schedule. Re-count against the machine.
Motor coil order: the 1·4·3·6 map and the two empty positions come from Jon's drawing, not from a measurement. Check the coils with a multimeter first.
Limit switch contact: the switch (Omron V-155-1C25) is SPDT with three tabs and the harness lands on two. Confirm which pair, COM+NC or COM+NO, against the board.