AIO cannot communicate with the CT clamp or external RS485 meter. Export limitation and self-consumption control will fail.
Common causes
CT clamp cable not connected to Meter/CT port on AIORS485 wiring fault (A/B swapped or disconnected)Wrong meter type in settingsCT clamp not closed properly around conductor
What to check
STEP 1
Check CT clamp cable is plugged into the correct Meter/CT port on the AIO unit. CT clamp must be closed fully around the incoming live conductor only (not around L+N together). Arrow on CT must face toward grid (away from consumer unit)
STEP 2
Measure resistance across CT leads — should read 240–250Ω. If open circuit, CT cable is broken. Check pins 1=Meter485A, 2=Meter485B at AIO Meter port. Try swapping A/B if comms is absent
Escalate if
Wiring confirmed correct and CT tests OK — AIO Meter port hardware fault, escalate
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