Microinverter Solar + Switchboard Monitoring

Getting Started
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Afternoon,

I’m going to be installing microinverter solarPv, and I’m looking for a way to monitor generation/import/export, as well as general house loads.

I’ve found a couple of resources, just wanted to confirm my thinking. Firstly, the Solar PV guide was a great help, and I should be able to install a Type2 setup easily as the microinverters will end up connected via their own circuit breaker added to the switchboard.

Queries I’ve got:

  1. The guide links to an emonPi device, but this only has two inputs. Can I achieve the same with an IoTaWatt (and selfhosting emoncms)?
  2. When I add more panels in the future, I’ll end up adding additional circuit breakers per MicroPV string, can I have multiple “generation” CTs around multiple CBs?

Thanks.

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  1. Yes, you can connect up to 14 inputs to IoTaWatt. You can configure either a self-hoted Emoncms server or upload to Emoncms.org.

  2. Yes. You can configure additional CTs on additional generation strings. You can then either upload their combined upload as a single number, individually, or both.

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Thanks @overeasy. One followup query:

  1. From the SCT-013 / 100A CT page, the comparison table implies it’s working range is 5A-100A, where the SCT-006 is 0A-20A. Does that mean the SCT-006 is better at tracking current under 5A?
  2. When is the IoTaWatt going to be back in stock? :slight_smile:
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I don’t see a noticeable difference with the IoTaWatt. The advantages that I see for the SCT006 are small size and low cost. Here is an SCT006 vs an SCT013 at about 1 amp (120watts at 120volts) on a bench test system. The load is my desktop computer.

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Over the course of a week, the two produce nearly identical kWh totals:

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25.2 vs 25.3 is 0.4%

That’s a question for the OEM folks. My part requires 5-6 weeks.

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Thanks for your replies @overeasy, much appreciated.