Bevan:
The wires on a phase coupler must be connected to each electrical phase (i.e. leg) on your system, and one wire is connected to the neutral bar.
There really isn't an easy way (without test equipment) to determine if your electrician actually connected your passive coupler to all phases (I think you said you had 3 phases). But, this is something that the electrician should definitely know. If he was aware that the passive coupler needed to be connected to each phase, he probably connected it correctly.
Robert
RCI Automation
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