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How to measure a single-phase 3 wire system?


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I'm having a Growatt SPF6000T-DVM inverter with a single-phase, 3-wire system (see attached image). My goal is to measure the Voltage and Ampere that goes to the main breaker panel. Is this possible with a 3EM, or doe I need to use two single-phase monitors? 

I checked the manual and searched the forum, but couldn't find anything on such a configuration. 

Thank you and best regards in advance. 

Screenshot 2024-06-29 at 07.14.50.png

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Most likely, the inverter is working with 230V only, ground wire is leading no current in this case. If so, a single current clamp is needed and a Shelly EM or pro EM-50. Terminal N of the Shelly is connected to one live wire, terminal L tho the opposite live wire. Shelly is supplied with 230V AC. The current clamp has to be mounted at one live wire.

Alternatively, if ground wire is leading current, you may use both current clamps of a Shelly EM or pro EM-50: Each clamp is connected at one of the live wires. Shelly is supplied with 115V AC: Ground wire at terminal N, one of the live wires to terminal L. You may have to turn of the clamps to adopt the phase shift of 180°. 

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