Need suggestions for troubleshooting battery charging from shore power

[D44]

So I finally got a chance to get back out to the Airstream. Started with the first suggestions.

Could it be as basic as blown 30a main fuses on the DC board?


Put two new ones in instead.

[D44]

Originally Posted by D44

So I finally got a chance to get back out to the Airstream. Started with the first suggestions.

Could it be as basic as blown 30a main fuses on the DC board?
Attachment 401307Attachment 401308

Put two new ones in instead.

Update:::

Yes I think that was it - last night when the solar shut down the SeeLevel was showing 12.9Attachment 401325

Tonight it is showing 13.5 which to me means the shore power is once again going through the converter.

Thanks to this group for all of the help and direction!
Walt

[GammaDog]

Fantastic! A couple of parting thoughts…

1. 12.9 volts is an odd reading. The batteries at their best put out less, the converter at its lowest (“float”) cycle puts out more. I wouldn’t do anything about that if it was mine except watch, notice (or even write down) voltages measured under various conditions and try to understand how the system is functioning. You have three chargers in your system (converter, solar and the 7 way plug), all three produce variable voltages. You have batteries that may be a load or a source depending, etc.. It’s a lot of variables! So, watch, learn and see if you can determine what voltages appear under what situations.
2. When I trained as a pilot I was taught to reset a circuit breaker once. If it tripped again, it’s signaling that there is a problem and resetting repeatedly is likely to make things worse, not better. Your two, 30 amp blade fuses blew once. If they go again, I’d dig deeper to understand why. Those not only provide overload protection, they also protect against reverse polarity. Who knows what caused them to blow once? If they pop again, you may want to explore why.

Happy camping!

[D44]

Originally Posted by GammaDog

Fantastic! A couple of parting thoughts…

1. 12.9 volts is an odd reading. The batteries at their best put out less, the converter at its lowest (“float”) cycle puts out more. I wouldn’t do anything about that if it was mine except watch, notice (or even write down) voltages measured under various conditions and try to understand how the system is functioning. You have three chargers in your system (converter, solar and the 7 way plug), all three produce variable voltages. You have batteries that may be a load or a source depending, etc.. It’s a lot of variables! So, watch, learn and see if you can determine what voltages appear under what situations.
2. When I trained as a pilot I was taught to reset a circuit breaker once. If it tripped again, it’s signaling that there is a problem and resetting repeatedly is likely to make things worse, not better. Your two, 30 amp blade fuses blew once. If they go again, I’d dig deeper to understand why. Those not only provide overload protection, they also protect against reverse polarity. Who knows what caused them to blow once? If they pop again, you may want to explore why.

Happy camping!

Yes I have thought about why they blew in the first place and will keep an eye on that. Thanks -

Walt

[uncle_bob]

Hi

Given current moving around here and there in the trailer, the in trailer monitors often will be off by more than a bit. In some cases it will be pretty easy to work out why. In others, it's going to be a head scratcher. Batteries "drift" from one voltage to the other. It takes a bit for them to stabilize here or there. There's also temperature, I suspect we can rule out it being 40F outside in this case ...

A multimeter on the battery posts or a good monitor direct wired is the best way to know what's going on.

Bob