MPPT controller at 13.64v - Blue Sea meter at 12.35v - Batteries not charging

[Openroad]

We have a 2022 Hawk that came with Overland Solar Panel and MPPT charge controller. Recently, I noticed that the MPPT controller display was never showing any PV current (always 0 watts). The MPPT display indicated that the solar panel was at 26.3v. I checked the solar panel and it is putting out about 5.75 amps. The Blue Sea systems 1733 DC voltmeter was showing the battery at 12.35v. At 12.35v, the charger should be pushing current to battery but it’s not. I put a meter to the battery’s (two 12v AGMs) and the meter showed 12.25v.

I suspected that the MPPT charger had lost its mind so I did a hard reset. I unplugged all the wiring, waited ten minutes and attached the wires (battery 1st). No change. At that point I thought OK the controller is blown get a new one. I purchased and installed new Victron SmartSolar MPPT 75|15 controller. The set up was easy and the software automatically chose the default 2 AGM deep cycle parameters.

So now I find myself in exactly the same place. The new controller always thinks the battery voltage is 13.79v and maintains the batteries in a state of “float” while my Blue Sea DC voltmeter and my multimeter shows voltage down to 12.35.

So finally, the question, what is going on? Why does the Blue Sea system DC voltage display show a battery that needs to be charged but the solar charger thinks otherwise? When I measure the voltage of the batteries at the battery wire terminal screws on the charger it shows 13.79v. However, when I disconnect the wires from the charger and measure the voltage the muti-meter jumps all over the place. I measured using two different multi-meters with the same unstable results. Does this indicate that I have a bad connection someplace? If that’s the case, how is it that the charge controller knew I have two 12v AGM batteries? Thoughts, suggestions.

 

[Jon R]

Sounds to me like the solar charger is not actually connected to the battery. It could be an open switch, circuit breaker, or fuse. Was any wiring work done immediately before the charging stopped?

 

[Openroad]

Sounds to me like the solar charger is not actually connected to the battery. It could be an open switch, circuit breaker, or fuse. Was any wiring work done immediately before the charging stopped?

Not that I know of. The burner had to be replaced but otherwise no. If the charger isn't connected to the battery how did the new one know about the two 12v AGM batteries during set up when I installed it ?

 

[Openroad]

Sounds to me like the solar charger is not actually connected to the battery. It could be an open switch, circuit breaker, or fuse. Was any wiring work done immediately before the charging stopped?

Jon, your reply gave me an idea and solved the problem. Turns out it was a loose connection. Your comment "has any wiring work been done" gave me the clue. Every Fall I remove the AGM batteries and put them on a trickle charger. My log showed that the problem occurred right after I installed the batteries this Spring. I decided to re-crimp the battery connectors and that did the trick. One of them was just loose enough to create a break in the circuit and moving the batteries initiated the problem.

In regards to the new charger, it turns out that the "default" setting for this unit is 2 AGM batteries so in this case (as you correctly noted) the charger was not seeing the batteries.

All is good now.... thanks for the guidance.

 

[Jon R]

Glad I was able to contribute a little to you figuring it out yourself. Good job troubleshooting!