Installing Multiple GEM120CT Meters (ID1 & ID2)
Overview
Where both grid and external PV generation must be monitored, two GEM120CT meters can be installed:
Voltage Reference Bridging
Both meters share the same voltage reference for accuracy.
|
Connection
|
Meter
|
Terminal
|
|---|
|
Live Feed
|
ID1 ↔ ID2 (bridge)
|
4 (L)
|
|
Neutral Feed
|
ID1 ↔ ID2 (bridge)
|
3 (N) |
CT Clamp Placement
|
Meter
|
CT Location
|
Arrow Direction
|
|---|
|
ID1
|
Main grid feed
|
Toward property load
|
|
ID2
|
PV string inverter live cable
|
Toward property load |
CT clamps must never encircle both live and neutral cables.
Communication Wiring
Both meters can share a communication line back to the inverter.
|
Meter
|
RS485 +
|
RS485 –
|
|---|
|
ID1
|
Port 10 → Inverter A+
|
Port 9 → Inverter B–
|
|
ID2
|
Bridged to ID1
|
Bridged to ID1 |
Only ID1 communicates directly with the inverter.
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