Communication error between power module and battery modules or power sensor.
Common causes
RJ45 cable between modules not connected or damagedWrong termination resistor placement (120Ω required at bus end)RS485 wires to power sensor transposed (Meter_A / Meter_B swapped)Power sensor not powered or failedWLAN dongle not seated in WLAN portTwo-column setup: cross-column RJ45 link cable missing
What to check
STEP 1
Check all RJ45 cables between modules are seated — click audible
STEP 2
Verify RJ45 terminator (120Ω resistors) fitted at correct end of bus
Escalate if
All wiring verified and fault persists — possible failed power sensor or WLAN dongle. Contact Anker support
Need full interactive diagnosis?
Faultpath walks you through decision trees, fault codes, and commissioning — built for solar & battery engineers.