checking number of panels on a string

[h2ofun]

I have solar edge inverters. I have 3 strings per inverter. What is the best way to determine how many panels are on each string? I can see the total, but do not seem to
be able to see how many per string.
My only thought was to turn off the inverter, and I guess could I measure each strong voltage to determine number of panels connected?

 

[wwhitney]

Have you asked the inverter? I would think it could tell you how many optimizers per input (not 100% sure). I infer you don't have the older style inverter with a screen and buttons. With the newer style, you can download an app to your phone and use it as the inverter user interface. I'm not familiar with those details, so look up the installation manual for your model.

Failing that, if you turn off the inverter, each optimizer goes into a safe mode where it produces 1V. So if you measure the string voltage, it will equal the number of optimizers on that string.

Cheers, Wayne

 

[Vines]

I have solar edge inverters. I have 3 strings per inverter. What is the best way to determine how many panels are on each string? I can see the total, but do not seem to
be able to see how many per string.
My only thought was to turn off the inverter, and I guess could I measure each strong voltage to determine number of panels connected?

Dont you have panel by panel monitoring through the Soalr Edge portal? That is how I would check.

Failing that take a multimeter to the string with the inverter off works as well. Each optimizer outputs 1v, so the voltage you read will also be the module count.

 

[h2ofun]

Have you asked the inverter? I would think it could tell you how many optimizers per input (not 100% sure). I infer you don't have the older style inverter with a screen and buttons. With the newer style, you can download an app to your phone and use it as the inverter user interface. I'm not familiar with those details, so look up the installation manual for your model.

Failing that, if you turn off the inverter, each optimizer goes into a safe mode where it produces 1V. So if you measure the string voltage, it will equal the number of optimizers on that string.

Cheers, Wayne

Yep, I log into the inverter and all it tells me is total number or optimizers for the inverter. I ask SE once while on the phone and they said nope, it does not give per string input.

So, that is what I was looking for. I turn off the inverter and measure each string voltage. I love its 1V per panel. Can I do this with the strings connected or would I need to take a wire off per string on the inverter?

 

[h2ofun]

Dont you have panel by panel monitoring through the Soalr Edge portal? That is how I would check.

Failing that take a multimeter to the string with the inverter off works as well. Each optimizer outputs 1v, so the voltage you read will also be the module count.

Yep, I can go into the SE portal and look at stuff. But from what I am seeing, this is what was put in by the installer, not what the inverter might be seeing.
Meaning, when one comes up and says module 2.0.27, well, I know no string has that many installed.
So, testing with a multimeter seems to be the only for sure way to do it. As I asked Wayne, can I do this with all the wiring connected and inverter off,
or do I need to disconnect one wire per string to test voltage. And when we say inverter off, how far back do I have to go? Just turn the knob on the front to off? Switch the little switch on it to off? Turn off the breaker to the inverter? Do not want to do something dumb.

 

[wwhitney]

First, disconnect the inverter from the grid, I'd use the closest AC disconnect on the grid side of the inverter. Then the dial on the bottom of the SE inverter (at least on my model) is a DC disconnect, turn it off. The cover is interlocked with that DC disconnect, so now you should be able to remove the cover. [It's 100% clear to me that you need to disconnect the AC side, but it's certainly OK. The best order of doing the AC and DC disconnects is also not clear to me, but I figure this way the inverter notices the loss of grid power and puts the DC side in a safe condition.]

Inside the DC disconnect you should find all the DC strings terminated. Hopefully you can take a voltage reading without determinating the conductors. I forget what kind of connector is used for landing the cables, but if it is something that covers the entire bare portion of the conductor, it should have a little hole in it which is a test port for your voltmeter probe. Ideally.

For more details, look up the installation manual of your inverter model, it has all this information.

Cheers, Wayne

 

[h2ofun]

First, disconnect the inverter from the grid, I'd use the closest AC disconnect on the grid side of the inverter. Then the dial on the bottom of the SE inverter (at least on my model) is a DC disconnect, turn it off. The cover is interlocked with that DC disconnect, so now you should be able to remove the cover. [It's 100% clear to me that you need to disconnect the AC side, but it's certainly OK. The best order of doing the AC and DC disconnects is also not clear to me, but I figure this way the inverter notices the loss of grid power and puts the DC side in a safe condition.]

Inside the DC disconnect you should find all the DC strings terminated. Hopefully you can take a voltage reading without determinating the conductors. I forget what kind of connector is used for landing the cables, but if it is something that covers the entire bare portion of the conductor, it should have a little hole in it which is a test port for your voltmeter probe. Ideally.

For more details, look up the installation manual of your inverter model, it has all this information.

Cheers, Wayne

Okay summary, turn of the AC breaker for the inverter in my generation panel. Turn the knob on front on inverter to disconnect. Take cover off, and see if I have voltage, like around 15 to 20 volts on a set of terminals, since that is about the number of panels per string. Great, thanks