Can an EM3500 be used to monitor 2 lines on a 3 phase system?

Issue
A customer needs to measure only 2 lines and 1 neutral coming from a 3-phase 4-wire wye service.

Product Line
EM3500 series.

Environment
Installation and commissioning.

Resolution

The meter system type must be left in 3-phase, 4-wire wye. All three phases must be referenced at the voltage inputs for the meter to do the total calculations. 1-3 CTs can be used to monitor the current and do power calculations, but the voltages must be present if the power is from a 3-phase 4-wire wye service.
The CTs must be on the same phase as the voltage input so the Power factor per phase is correct. It is recommended to connect the CTs to the L1 and the L2 current inputs in the meter.

Per-phase voltages (Vln a, Vln b), currents (I a, I b), power (kW a, kW b) and energy (kWh a, kWh b) will be correct. Also the
Total power (kW tot, KVAR tot and KVA tot) and energy (kWh tot, KVARh tot and KVAh tot) will be correct.
Average current (Iavg) will be trivial since 3-phase current is expected including that of the L3, but this is zero.

Also consult the installation guide for more information on the EM3500 meter.

Đã phát hành cho: Schneider Electric Việt Nam