Panel Underproducing

[Tanuki]

Hello everyone.

I have a 160w panel hooked up a Victron 100/15 MPPT controller and everything seems to be operating properly (except the phantom "load output" that I can't find.

My problem is that the highest wattage I've seen my panel pushing (according my the victron app connected via bluetooth) is about 55w in full sun.

It's cloudy today and it's only getting up to 42w. I just used my multimeter to test the voltage coming out of the panel (at the connectors) and I got 21.1 volts and 1.2 amps.

Does anyone have some troubleshooting ideas for me or any tips to isolate the problem?

[ewarnerusa]

Is your battery sufficiently discharged to warrant your panel's full load? What is the battery voltage?

[Tanuki]

That's a good thought. My batteries are pretty topped up. The only thing that was throwing me off of that trail is that when my refrigerator cycles on, the panel isn't even producing enough power to cancel it out.

[gustavpumper]

It looks like your solar panel has some problem. To troubleshoot, it's always recommended to check out the connection first. Under a perfect wiring condition, pick up a sunny day.

I cannot come up with 42W according to the spec provided. 21.1 X 1.2= 25.32W, not even close to 42W.

Have you ever tested the panel in a perfect weather day, and is this a brand new solar panel? Most of the solar cells would emit roughly 80% to my knowledge, but 40W is only one quarter to that.

If this is within the warranty, I guess there is no other way but to claim to whom you brought it.

[wayne23836]

You mention "load output", some controllers only use the load terminals for a relay or night lights. is the battery connected to the load or the + and -. Don't know if this even applies since you are getting some output, just not sure at which terminals.

[Tanuki]

The numbers are fluctuating pretty bad while I'm taking measurements so they may not all add up but I know that I'm not where I should be. The seller has suggested that I open up the junction box and take readings from there. I'll be doing that tomorrow when I get home. The phantom load output has also fixed itself, I'm thinking that maybe my controller just needed some timed to adjust.. I do have my loads connected through the load output but it's supposed to be rated up to 15a which is more than enough for me.