ECN Forum Forums General Topics of the Trade Non-US Electrical Systems & Trades polyphase metering single phase CT

If you had a CT on just one HV phase, it would register for more than one LV phase anyway, as the 11kV primary is delta and the 240/415 secondary is wye.

I agree, the whole idea sounds completely cock-eyed to me. I've never heard of just metering one phase of the supply.