Solar problem

[Theiznezz]

The past 2 days after the sun goes down my charge controller starts going up in voltage
. it slowly goes up 16v 17v 18 v. Anybody know what's going on?

 

[John61CT]

Start by stating your equipment, ideally with links.

Next, where are you measuring volts / amps, and with what instrument(s)?

Are the readings the same at the bank, as opposed to the SC output terminals?

Have you isolated the bank/SC/panels from circuits containing other devices, both loads like inverters, possible charge sources?

What happens when you disconnect the panels?

 

[Theiznezz]

Yes its isolated. I've had this setup for over a year with no problems. I have 3 100w renogy panels. A sunforce charge controller and 3 dekka marine master batteries.
The voltage reading on my charge controller is the one giving me these readings. I have another meter hooked up that gives me a different reading. That one is accurate.

So I'm not sure why my charge controller is giving this reading...

 

[Theiznezz]

I disconnected the panels. I have a recessed controller so I had to take apart the walls to get to the terminals.it did nothing. Good news. My panels are safe.

I kinda figured out the issue. For some reason my blower fan ac fan fuse keeps blowing. Like every 6 months or so. I think this all has something to do with the battery isolator. I put a new fuse in and the voltage dropped on the charge controller. Not sure why this keeps blowing fuses. Maybe the battery relay is stuck on closed?

 

[Theiznezz]

Still doesn't explain why the other voltage meter reads normal

 

[Theiznezz]

I played around with the isolator and the switch still works. I disconnected it completely from the batteries and the voltage reads 14.8v on the charge controller. So just the charge controller hooked up to the batteries its reading 14.8v

Its night time so now solar coming in. I checked the wiring and it looks good.

Maybe if I smack it a few times with a hammer that will work

 

[John61CT]

I never trust cheap charge source regulators, especially their meter readings.

 

[Weight]

One year is pretty good for an inexpensive controller.

 

[Theiznezz]

Yea. I'm thinking its the controller starting to go too. I just ordered a mppt renogy 40 amp controller last week so perfect timing I guess.

Ive had this one for 3 years almost