I have heard various ideas about AUS installations. The two I heard were (not from official sources, one was a talk from a guy in Melbourne):
- Installation of CT coils must be done by a licensed electrician
- Installation of the monitoring device must be outside the meter box
I actually didn’t find any real information about this. All the info was about CT coils used by power companies for installations with really high current usage and there are lots of strict rules here:
Its hard to parse that entire document, but I dont think it really deals with smaller personal power monitoring devices like IoTaWatt and Efergy.
I also looked at Efergy installation manual:
Again it is not clear, but I assume it means that a licensed electrician must install the CT coils, but doesn’t mention anything about the Efergy monitoring device being installed outside the meter box.
Where did you hear about this rule that the IoTaWatt needs to be outside the meter box?
Also, is it feasible to use a single wire for the common CT bias of all CT’s, and get 7x CTs connected to the one CAT5?
Not sure about noise introduced doing this. Don’t imagine it would be all that different to using 2x wires for each as there is no differential used for the twisted pair anyway so probably has similar characteristics to obtain 7x instead of 4x out of the one cable.