CCA cannot find the TAP. All TS4 units will be unable to receive keep-alive signal.
Common causes
RS-485 cable between CCA and TAP faulty or reversedTAP RS-485 cable in same conduit as PV DC cables (EMI)Insufficient 24VDC power at TAP from CCALong RS-485 run causing voltage drop
What to check
STEP 1
Run TAP Test in EI App > Settings > TAP Test. Check RS-485 A/B polarity — not reversed.
STEP 2
Measure 24VDC at TAP terminal. Ensure TAP cable is NOT in same conduit as DC power cables.
Escalate if
Power confirmed, polarity correct, cable not in DC conduit — contact Tigo support.
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