EG4
EG4 inverters (18kPV, 12kPV, 6000XP, 3000EHV, FlexBOSS, GridBOSS, MidBOSS), batteries (LifePower4, LL, PowerPro, WallMount) and balance-of-system parts; a DIY-leaning brand sold through Signature Solar
Covered equipment
Failures by component
inverter control board and firmware
- Inverter stuck in Standby, or a setting changed, after a firmware update
- 3000EHV charges battery but won't discharge it
- Inverter shows no display, no power indication
- 6000XP shuts down before sunrise, false Warning 25
- New unit arrives with a wire hanging loose
- Battery drains toward empty ignoring visible settings
- DKST setting reverts to YES within an hour
- 6000EX shows Error 32 during firmware update
- Inverter settings revert after power cycle or toggle
- Quick Charge disables all charge schedules
- One fan runs full speed despite low settings
battery management system (BMS)
- Battery BMS goes fully dead, no response
- Battery SOC drops suddenly to 0%, triggers charging
- Third-party inverter can't reach, or misreads, EG4 battery
- Battery reports falsely as discharging above 328A
- 314Ah WallMount charges at only 15 A when warm
- One battery's SOC drops while others stay full
- LifePower4 batteries click off in cold weather
- LifePower4 batteries stay idle after a low-voltage event
- Battery BMS cuts out when a large load starts
- Battery alarms when breaker closed after BMS on
WiFi dongle and EG4 Monitor Center
- WiFi dongle stuck offline, won't pair
- Monitor app shows wrong or stale data
- Monitor drops the per-battery detail table
- Ethernet dongle stays offline after Wi-Fi drops
battery communication port
- Inverter shows 0% SOC, no battery communication
- Inverter drops output every 10-15 minutes, Warning 27
AC output / EPS inverter stage
- 18kPV faults Vbus Over Range from specific loads
- 6000XP shows all-green status but no AC output
- Inverter backfeeds grid despite export being disabled
- Lights flicker or GFCI breakers trip on inverter power
- Neutral-ground bond missing or doubled after install
- Inverter throws EPS overload warning under light load
- 6000XP briefly cuts loads right at 100% SOC
- 6000XP oscillates in and out of bypass mode
- EPS overload with one leg over its limit
- Backup loads panel dead with grid present
generator / AC input integration
- Generator powers loads but delivers no charge current
- Lights pulse with generator, inverter later dies
MPPT / charge controller
- Charge voltage stays at bulk instead of float
- 12000XP PV input stuck near 120V every morning
- Battery won't charge despite normal PV readings
- MPPT inputs stay stuck near zero after clouds
parallel (CAN) bus
current transformers and consumption metering
GridBOSS/FlexBOSS parallel link
- GridBOSS shows offline, W030 CAN Loss error
- GridBOSS trips relays or cycles power on grid transitions
- Rapid shutdown cuts the whole home, or only one inverter responds
battery-to-inverter and battery-to-battery comm cable
- New batteries fail to communicate with older bank
- Nearer battery cycles faster than the farther one
- LifePower4 V2 trips rapid shutdown when cabled to V1
- Only the leader WallMount battery shows in the app
PV strings and input terminals
- PV string reads a fraction of expected voltage
- PV terminal block found melted and charred
- Inverter shows PV Isolation low every morning
Chargeverter AC-to-DC charging path
- Chargeverter shows correct voltage but zero current
- Chargeverter ring terminals don't fit 3/8 in studs
- Chargeverter reads State of Charge Lost