If you monitor solar with iOS device – you need a negative multiplier

[Cooper2072]

Thought I would share what I discovered through trial and error.
We have solar on our home and monitored the solar with one of the expansion pack inputs. With an iOS devices there isn’t direct capability to set this to a negative value. The reason you must set this to a negative value is if you begin to generate excess on any interval, the MAIN will not flop to a negative value. The positive expansion pack input monitoring the solar just increase the load of the main in the shape of the expansion pack input. In other words, it seems the expansion pack input overrides the total of the main and and keeps it looking like all load.

If you flip the solar input to a negative multiplier, this fixes the issue and the MAIN will now go true bidirectional when looking at the values.

For iOS users, there is no minus sign on the input screen to set the multiplier to a negative value.

Here is what I did: I put a minus sign in text somewhere else – anywhere else – and copied just the minus sign as text. I then pasted this ahead of the numeric value of the multiplier. Saved. Success. The input was now negative and my MAIN was true bidirectional.

[New2Me]

I have been using the negative multiplier on my solar circuit, but I’m not too sure about the readings. I have Enphase micro-inverters that output to a double pole breaker, so I put an expansion pack circuit CT on each leg, and set the multiplier at -1. I didn’t think that the output was as high as I was expecting, so I changed it to -2, and it looks more like what I’m expecting, but now I see that there is a constant minimum reading of around -2.54 amps on each leg of the solar breakers at night, and it seems to make the main reading go negative too? I’m really sure that the main is not now the ACTUAL reading from the 2 large CTs, as it appears to be a sum of all of the expansion CTs? I wonder how the main CT circuits are multiplied, and why aren’t they shown individually like the 8 expansion circuits, so that you can check load balance?

[Emporia Support]

Thank you @Cooper2072 and @New2Me for your questions and comments.
Good catch that the iOS app does not currently support “minus” signs in the text input. We’ve passed that down to development.

@Cooper2072 – I’m surprised at your comment regarding a multiplier on the expansion influencing the readings on your main. The data on all of the inputs are independent of one another, and placing a multiplier on an expansion circuit should not affect any readings on the “Mains” graph.

@New2Me – I’d like to address a couple of items –
1) Regarding why our device shows a load at night on solar circuits:
This answer gets into the weeds a little, so please bear with me. Our device measures Apparent Power. In circuits with a poor power factor (like inverters that are in “sleep” mode), the device will read the current running through the wire, and multiply this current by 120 V to get to Watts.
In reality, the inverter is actually drawing very little Real Power, because the Voltage and Current are not in phase. Our current hardware does not take this into consideration. Here’s a blog link about this if you’d like to know more.

2) Regarding checking the current through each of the mains:
This feature is on our roadmap, but right now we don’t have a specific release date. We appreciate your feedback and hope you understand that we’re working very hard to prioritize the many enhancements that have been requested.

• This reply was modified 4 years, 9 months ago by Jim @Emporia.
• This reply was modified 4 years, 9 months ago by Jim @Emporia.

[charlie]

Is this still the case and also do you need a clamp on both legs?

[Jim @Emporia]

@charlie, the iOS app still does not support entering negative numbers, however some customers have been able to get one in the app by copy/pasting a -1 from another app. As with any expansion clamp, you can use a single clamp and use the multiplier to double your reading.

[ds679]

Sounds almost like you’ve got the CT’s installed backwards?

[Author]

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