New Install with 2 pairs of mains wires - US

I’ve got a couple questions:

  1. The photo above is my US / North America home service panel. It has 2 pairs of wires coming from the utility meter side connected to the bottom 4 circuit breaker positions. To properly deploy the IotaWatt, do I just clamp 2 CTs on the bottom 2 wires and configure IotaWatt to double up the numbers when logging data?

  2. To safely install the CTs, I should make sure the CT clamps are plugged into the IotaWatt before so that I’m protected by the burden resistors, which are in the Iotawatt device itself?

  3. I bought a 6x6x3.5 IP67 junction box to house the IotaWatt along the exterior of my home right next to the service panel. Do you think this’ll be big enough? I’m thinking about soldering wires + XT60 connectors + shrink wrap for the 5v DC adapter and the 9v AC ref transformer adapter to bypass the need of installing an outlet. Do you have any suggestions on space saving techniques? or should i just go with a bigger junction box and have an outlet installed inside it?

Those Siemens panels are a problem. I doubt you could get CTs on those wires and doubling is not very accurate. It looks as though there is no seal on the panel below the meter. If you can open that up you may be able to get at the incoming feeds and put CTs on them there. Otherwise you would need an electrician to pull the meter to get at the feeds. Probably not an option.

It’s a good idea to have the CTs plugged in if installing on a live cable, but the AccuEnergy CTs and Echun CTs have protection diodes so it’s not necessary.

That box sounds small. I usually recommend the Orbit sprinkler control box. It has a duplex plug inside, is rated for outdoor use and has a lock.

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Thanks for the feedback. I’ll see if I can wrap the CTs around a pair of the legs. There might be enough space behind the circuit breakers. If that works out, I’ll see if I can calculate the error for doubling up the numbers… maybe it’s consistent enough to just apply a multiplier? In any case, I’ll report back what I end up doing.

I found the control box you suggested on amazon as Orbit 57095 Outdoor-Mounted Controller Timer Box Cover, Grey