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What system type should be used for monitoring 2 phases (legs) of a 3-phase 4-wire system?

One solution is to configure the device for a system type 40 (3-phase 4-wire with 3 CTs). Then wire in all three voltage phases and connect the neutral. Then wire the two current phases (CT) to the corresponding current input. The third phase current input will not have a current transformer (CT) connected. More detail should be discussed with your technical support representative before assuming that the above solution covers each scenario.
The phase current will read 0 for the phase that does not have the CT connected.
The individual KW and total KW will be correct.
All total values will be correct like Energy, power, Kvars, and etc.
Only 3 phase average Voltage will be correct. All other average readings can not be used because 0 will be part of the average value.
There will be a current imbalance since one phase will have zero current.

This applies to the Series 2000, 3000, 4000 Circuit Monitors (CM2000, CM3000, CM4000) and the Series 200, 600, 700, 800 Power Meters (PM200, PM600, PM700, PM800)

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    Original Author: PH
    All content © 1992-2010 Schneider Electric

Legacy KB System (APS) Data: RESL191911 V2.0, Originally authored by PhHa on 05/15/2008, Last Edited by DaMi on 11/02/2010
Related ranges: PM800 series, PM700 series, PM600 series, PM200 series, CM4000 series, CM3000 series, CM2000 series, Engineering Knowledge Applied to Power Management
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