Check first
- What was on the backup at the moment of failure? Compile the peak load history with the customer. One appliance too many is the leading cause.
- Battery state at the time — an empty bank or one parked by a reserve threshold has nothing to give. If the battery is the issue, go to Battery Not Discharging first.
- Which device tripped — the inverter’s own alarm, the backup MCB, or an RCD? An RCD trip points to Nuisance Tripping.
Causes
| Cause | How to confirm | Fix |
|---|---|---|
| Backup overloaded | Kent M1: E202 (off-grid overload) / E405 (battery output overload) · Kent G3: Over-Load / OV-ILLC; clamp-meter during load steps confirms | Move heavy loads to the grid side; resize the essential panel per Essential Loads |
| Motor start exceeds backup capability | Trips only when a compressor or pump starts — not under steady load | Kent M1: size to rated power only — no motor-start surge headroom is promised · Kent G3: overload capability is 2× rated for 10 s — verify the real inrush fits within this window |
| Battery empty or parked by threshold | SOC was at cut-off when the outage hit | Review the reserve strategy on the platform settings page; enable grid-charge deliberately on outage-priority homes |
| One phase overloaded (Kent G3 only) | Trip correlates with a single heavy phase; other phases are lightly loaded | Rebalance loads across all three phases; per-phase limit applies — do not promise more than 100% of per-phase rating on any single phase |
| Loads drop on transfer then return | Sensitive loads reset at every outage | The pass criterion is “loads ride through” — verify with the black-start test; do not quote a millisecond figure for Kent M1 |
| Grid supply landed on the Backup port | Wiring trace; history of “worked once then died” after a grid outage | Installation fault with hardware consequences — isolate immediately and escalate; never re-energise as-is |
| Backup voltage fault | Kent M1: E200 (output V high) / E201 (output V low) | E201 usually means the source is exhausted (PV + battery low); check energy state and settings per the alarm guidance |
Prove the fix
Re-run the black-start test with the real essential loads: open the grid breaker, confirm loads ride through the transfer, verify a clean reconnect when grid returns, and confirm no RCD trips. Photograph the display during backup operation and log the measured backup load. 📷Escalate when
- Overload trips repeat with a measured load that is inside the platform’s rated backup current.
- You have any suspicion the grid supply ever reached the Backup port.
- Transfer behaviour remains erratic after all of the causes above are cleared.
Escalate to Kent New Energy service only — through your registered Kent partner channel or the Kent service desk details on your work order. Do not contact any third-party or component-manufacturer support line for a Kent-branded system: tickets outside the Kent channel are not tracked, not covered, and can void warranty handling.