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Ten questions from the Battery & BMS group. Work through all ten before scrolling to the key. Suggested pass mark: 8 / 10. Each miss points to a source page — re-read it, not the whole group.

Questions

1. In a closed-loop BMS setup, the inverter display shows:
  • A. A fixed default SOC of 50 % until fully charged
  • B. Live SOC from the BMS and the battery model name
  • C. Only voltage — closed-loop does not transmit SOC
  • D. SOC rounded to the nearest 10 %

2. The communication protocol that carries BMS data between the Kent Lithium Battery and the inverter is:
  • A. RS485 (Modbus)
  • B. RS232
  • C. CAN
  • D. Ethernet

3. On the RJ45 BMS port of the Kent inverter, CAN-H is on pin ___ and CAN-L is on pin ___:
  • A. Pin 1 and pin 2
  • B. Pin 3 and pin 6
  • C. Pin 4 (CAN-H) and pin 5 (CAN-L)
  • D. Pin 7 and pin 8

4. The Kent Lithium Battery uses a mirrored RJ45 pinout. The correct communication cable between the pack and the inverter is therefore:
  • A. A straight-through RJ45 patch cable — same as a network cable
  • B. Any CAT5 cable under 3 m
  • C. A crossover cable — CAN pins 4 and 5 are reversed between pack and inverter
  • D. A USB-A to RJ45 adapter

5. The recommended SOC range for storing a Kent Lithium Battery pack when the system will be idle for an extended period is:
  • A. 0–10 % — empty is the safest storage state
  • B. 30–60 % SOC
  • C. Always charge to 100 % before storage
  • D. Any SOC below 80 % is acceptable

6. When the BMS communication link is lost, the inverter displays a frozen SOC value. This indicates:
  • A. A battery calibration problem — the BMS has lost its cell data
  • B. A communication problem — check the cable, pinout, and seating before touching any settings
  • C. The battery is at end of life
  • D. Normal behaviour when PV is not producing

7. The Kent G3 Battery Healing switch is used to:
  • A. Charge the battery to 100 % from the grid without allowing discharge, restoring SOC accuracy
  • B. Balance cells by forcing a full discharge to empty
  • C. Replace faulty BMS firmware over the CAN link
  • D. Run an automatic monthly capacity test

8. A dormant Kent Lithium Battery pack that has gone into deep-discharge protection should be woken using:
  • A. A bench power supply connected briefly to the pack terminals to inject a small charge
  • B. The official inverter function only — Kent G3 Battery Wakeup switch / Kent M1 Activate Bat
  • C. Shorting the battery terminals briefly to trigger the BMS reset
  • D. Holding the pack power button for 30 seconds

9. The Kent F1-5120 battery pack maximum continuous discharge current is:
  • A. 100 A
  • B. 120 A
  • C. 60 A
  • D. 40 A

10. In a multi-pack Kent Lithium Battery stack, the CAN communication cable runs from:
  • A. Every pack to the inverter, in a star topology
  • B. The master pack to the inverter — the master handles communication for the whole stack
  • C. The last pack in the string to the inverter
  • D. Pack to pack only — the inverter reads SOC via voltage

Answer key

QAnswerWhy
1BClosed-loop BMS means live SOC and battery model name are shown on the inverter display. If the model name is missing or SOC is frozen, communication is broken.
2CCAN is the lithium battery communication link on both Kent platforms. RS485 is used for meters and some older packs — not for the Kent Lithium Battery BMS.
3CThe inverter BMS RJ45 port has CAN-H on pin 4 and CAN-L on pin 5. The Kent battery pack mirrors this, which is why a crossover cable is needed.
4CThe Kent Lithium Battery pinout mirrors the inverter — CAN-H and CAN-L are on the same pin numbers at both ends. A crossover cable swaps them correctly. Use only the labelled Kent comm cable.
5BStorage SOC is 30–60 %. Storing empty causes deep discharge; storing at 100 % accelerates calendar degradation.
6BA frozen SOC is a communication symptom, not a calibration problem. Check the cable label, continuity, RJ45 seating, and pinout before changing any setting.
7ABattery Healing on the Kent G3 charges the pack to 100 % from the grid without allowing any discharge, which re-anchors the BMS SOC calculation.
8BUse only the inverter’s official wakeup function. Jump-charging from a bench supply or shorting terminals can damage the BMS or the pack and voids the warranty.
9CThe F1-5120 maximum continuous discharge current is 60 A. System design must not demand more than this from a single pack.
10BOne CAN cable runs from the master pack to the inverter. The master manages communication for the whole stack — the inverter does not need individual connections to each pack.