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One cable determines whether a Kent lithium installation communicates at all. A straight RJ45 patch lead looks identical to the correct cable — and fails every time on this pairing. Run these checks before every power-up.
For trained and authorised installers only. Comm-cable work happens adjacent to live battery terminals. Battery Safety rules apply throughout — see Battery Safety.
A straight RJ45 patch lead will never communicate on a Kent lithium pairing. The Kent battery carries CAN-L on pin 4 and CAN-H on pin 5; both Kent inverters expect the opposite. You must use the labelled Kent battery comm cable — pins 4 and 5 are swapped end-to-end. The symptom of a straight cable is a battery comm fault at first power-up, every time.

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The pin card

Pins 4 and 5 cross between the battery end and the inverter end. All other pins run straight.
RJ45 pinKent battery endInverter BMS end (G3 and M1)
4CAN-LCAN-H
5CAN-HCAN-L
The correct cable is straight on all pins except 4 and 5, which swap — that is the labelled Kent crossover cable. One such cable per bank, running from the master pack’s CAN port to the inverter BMS port.

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Before power-up: three cable checks

Run all three checks with the system isolated and the cable connectors accessible.
1

Label check

Confirm the Kent crossover label is physically on the cable in use. A generic LAN patch lead anywhere in the battery comm path is an automatic fail — remove it and replace it with the labelled Kent cable. Photograph the label in place.
2

Continuity check

With the cable off-line and both connectors in hand, meter it against the pin card above:
  • Pin 4 on one end must read continuity to pin 5 on the other end.
  • Pin 5 on one end must read continuity to pin 4 on the other end.
  • All other used pins must read straight (pin 1 to pin 1, and so on).
3

Seating check

Both RJ45 connectors must click fully home — at the master pack’s CAN port and at the inverter BMS port. Confirm the run is strain-relieved and routed away from DC power cable pinch points.

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Field fallback — re-terminating one end on site

If no labelled Kent cable is available, both source manuals authorise the same fallback: cut off the RJ45 at one end, re-crimp it with pins 4 and 5 swapped, then re-run the continuity check and mark the cable clearly as a crossover.
Never attempt to fix a comm fault through the menus. No battery-model selection, protocol entry, or settings change compensates for a wrong cable. Cable first, settings second — in that order, always.
Pending Kent validation. [KNB-VAL-05] The F1 cable-kit contents and the exact battery-brand label shown on the Kent M1 screen are under confirmation with the Kent battery team. The pairing, minimum-pack matrix, and the 4–5 crossover rule are confirmed. Until published here: use only the labelled Kent battery comm cable, and verify any field-made crossover cable against the pin card above before power-up.

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Multi-pack banks

When running more than one pack in parallel, follow these rules:
  • Each pack needs a DIP-switch address set before power-up. Record the address map on the commissioning sheet.
  • Only the master pack connects to the inverter — one crossover cable per bank, regardless of pack count.
  • The maximum bank size is 16 packs.
Set every pack’s address before any pack is connected to another. Addressing live packs mid-installation is a preventable mistake.

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Common mistakes

Physical fit is irrelevant — the pinout is wrong. A straight patch lead guarantees a comm failure on this pairing.
The swap belongs at one end only. Re-terminating both ends makes the cable straight again, which fails the continuity check and fails at power-up.
The inter-pack link follows the battery wiring guide, not this pin card. The crossover cable runs from master pack to inverter only.
An unlabelled field-made cable will be “fixed” back to straight by the next technician on site. Mark it clearly and permanently.