Solar controller questions/help

[TravisG]

First I would like to apologize if this is a dumb question. We installed two 165 watt solar panels and a charge controller wired to two 12 volt batteries in parallel this winter. Charging light came on and I haven't really given it much thought until today.....

Today I went into the trailer just to look around and check on stuff and to check the charge controller. The charger wasn't indicating that it was charging and read that it was at 13.9 volts. The little tattle tale lights on the wall were only showing three out of four lit up.(I know they aren't very reliable btw) I thought I would check at the batteries to see what voltage they were putting out. Pulled off the covers and they are reading 11.89 volts.

My question is this, shouldn't in theory the charge controller be reading the same voltage as my meter did when I checked it with my meter?

A couple of readings from the charge controller in case it helps and I am doing something wrong...
Load 00.0 Amps
Charge 00.0 Amps
Battery SOC 100%
Charge off 31.7 Volts
Load off 10.5 Volts
Load on 12.5 Volts

[time2roll]

17 volts in and less than 12v out is a defective controller IMO.

https://www.solarblvd.com/products/morningstar-sunsaver-ss20l-20a-12v-charge-controller/

[red31]

AFIK this controller has one set point Full Charge Cut the default is 13.7v

In float it should have the battery @ 13.7v, make sure it is set correctly.

Camping 14.8 would be good, in storage 13.7 is ok.

In BULK, probe the connecting terminals, they should be batt voltage (both panel and batt & battery posts) and on the rise till they hit the set point 'Full charge cut'

Eventually (when the batt gets to set pt voltage) the panel terminals voltage should rise as high as 21v (for a 12v panel and may jump around).

In float the panel v will be high and the batt terminals should be set pt voltage as well as the batt posts.

[TravisG]

I checked it this morning before heading out the door at the controller itself. The light was flickering so that means it was float charging it was jumping between 17.6 Volts and 18.5 Volts. Voltage out to the battery was steady at 11.7 Volts. Didn't even think about checking the actual voltage at the battery.
Like was said above, the controller gets it's power from the battery and the disconnect is on.
Red31 I will look into those controllers you and westend mentioned. Thank you. You mentioned changing the full charge cut from 13.7 to a higher voltage. What would you suggest bumping it up to? Just bump it up until the batteries are actually at 13.7?

[red31]

the controller gets it power from the battery so it is connected to the battery.

http://www.naturepowerproducts.com/doc_db/60028_28amp_charge_controller_manual_eng_fre.pdf

Charging Status: (LED = RED)
ON: bulk charge
Flickering: float charging
OFF: battery is fully charged/no charge from solar panel

LCD Display: Shows the battery voltage, charging current
and loads’ current in 5 second internals, during operation

I'd measure at the connecting terminals, solar & battery and compare to battery post measurement. All battery connection should be clean.

I'd also change the Full Charge Cut (Default) 13.7V to much higher, take that back I'd replace this controller with a grape bluetooth and monitor via cell phone app from grape. or any other controller that has charging set pt of 14.6v

[westend]

I'd suggest to return it and get a Morningstar controller. You should be able to get a PWM controller from MS for about the same price.

One thing that alerts me that this is not a very robust controller: "Max solar input 20V".

[Joe417]

If your charge controller is showing 13.9 and the batteries measure 11.89 I would think the controller isn't connected to the batteries.

Not sure how it is wired but is the battery disconnect turned off and breaking the solar circuit or maybe a fuse in the solar circuit.

The batteries should measure about the same at the battery or directly at the controller.

Better plug the camper in and get it charged before your trip. Even if you get the solar straightened out it may not have enough time to charge the battery, depending on the sun you get in the next day or two.

[TravisG]

Yes Sir the sun was out when I checked it. I will try and check the input/output voltages tomorrow but leaving for a race for the weekend. It is a Nature Power 28 amp charge controller Model 60028. Not that impressed with it so far but this is my first time ever really messing with solar so I wasn't sure what to expect.

Thank y'all for the replies btw.

[time2roll]

At the controller what is the input voltage from the panels?
And what is the output voltage on the controller terminals?
May as well post the controller make and model.

[2oldman]

Yes. Apparently a disconnect between the batteries and the controller. I don't know what charge off, load off and load on mean.

Was the sun out during this check?