In a multi-unit EP parallel installation, the master battery cannot assign addresses to all slave units.
Common causes
LINK IN/LINK OUT chain cable missing or not seatedWrong unit designated as MainUnits are different EP models (incompatible parallel)
What to check
STEP 1
Check LINK OUT of Main unit connects to LINK IN of first Slave, and LINK OUT of first Slave to LINK IN of second Slave, etc. All cables must be the supplied CAN patch cable
STEP 2
Confirm all EP units are the same model (e.g. all EP5 or all EP10). Mixed models cannot be paralleled. Check that the Main unit is the one with the CAN cable to the inverter
Escalate if
All cables correct and models match but addressing still fails — escalate
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