[GuyGoldy41!]

I followed the diagram I found online and for some reason my house battery isn’t charging. It did show 3.25ah on the battery monitor when I first tuned it on, but now it is at zero or slightly negative. Any help is appreciated! Note: I bought fuse boxes for the dc to dc charger, but the fuses didn’t come in so I am trying it with these little 60amp fuses.

 

[GuyGoldy41!]

We need more info on your setup to really help out. What charger are you using? What type of batteries?

The Dc to DC is coming from my van battery, the house battery is lithium.

here is how it is setup:
Car Battery - DC to DC charger- victron lynx distributor

house battery to shunt, to Lynx, to chassis ground.
I don’t have a charger outside of the van alternator.

 

[GuyGoldy41!]

That’s embarrassing I thought I posted these with the first comment

 

[GuyGoldy41!]

No offense a

What kind of battery? You may be locked out by the BMS. Have you checked that you are getting power to the DC to DC converter? And out of the converter? Try hooking up the battery to a plug in charger and see if it accepts a charge.

Really, truly no offense but you have a bunch pf wiring no-no's in that picture. Once you get the charging issue sorted out you should look into correcting them as long term you may have issues.

No offense at all, this is my first time doing something like this. I tried to find a diagram to follow and found this one below. I figured I would upgrade in the future, but was just trying to get power to a maxx air fan, two outlets, and a few ceiling lights.

 

[GuyGoldy41!]

Also

No offense a

No offense at all, this is my first time doing something like this. I tried to find a diagram to follow and found this one below. I figured I would upgrade in the future, but was just trying to get power to a maxx air fan, two outlets, and a few ceiling lights. View attachment 173816

It is a Chinns battery.

 

[GuyGoldy41!]

Start by testing for voltage as @harryn says to do. First thing is to find out how far towards the battery power is getting.

A couple of the things I see in that picture are unsupported wires and no loom. In a vibration rone enviroment those things will lead to problems. And potentially failure or even fire.

As to the Chinns battery I am not familiar and don't know how the BMS operates. I would be doing anything I could to jump some power in there, it is not good to leave them sitting that low. Do you have any access to a plug in charger that could be used to feed the poor things?

I do have a charger, I will toss it on there. One question, my BMS says I am at 12.1, is my battery fu

Start by testing for voltage as @harryn says to do. First thing is to find out how far towards the battery power is getting.

A couple of the things I see in that picture are unsupported wires and no loom. In a vibration rone enviroment those things will lead to problems. And potentially failure or even fire.

As to the Chinns battery I am not familiar and don't know how the BMS operates. I would be doing anything I could to jump some power in there, it is not good to leave them sitting that low. Do you have any access to a plug in charger that could be used to feed the poor things?

I will toss it on a charger. The battery shows 12.1 volts right now. They should be around 13 correct? Thanks for the info on the wires too. I am going to isolate the system and order the wire supports and boxers for the fuses.

 

[GuyGoldy41!]

HArd to say what shape the battery is in. If this is the first time it has been run down like this hopefully it will be ok. How did the charger work out? Is the battery accepting a charge?

The battery fully charged, I also checked my connections and they are all getting power. When the battery was dead, I did notice the little green connector on the Dc to DC was not inserted fully.

I think the battery died and it wouldn’t charge After I pushed the connector in. I am reconnecting everything and trying it again.
Note: I found some fuse cases to prevent anything from being exposed and I am placing some wire supports.

 

[GuyGoldy41!]

Be aware you appear to be running a 400 amp Mega fuse with 4 awg wire
View attachment 173880

I am based on the diagram. Should it be less? The other connection points are all 80amp

 

[GuyGoldy41!]

4 AWG is good for 85 amps (depends on the tables, that might be in conduit). The fuse, not the wiring, should be the weakest link.

...and the diagram you linked to calls for 4/0 AWG, which is entirely different than straight 4.

4/0 has around 5x the cross-section of copper. It's HUGE wire.

That’s good to know, I’ll reduce the fuse, or should I increase the wire?

 

[GuyGoldy41!]

I

I wonder if your problem is in the software for the DCtoDC charger. using the app from your phone you can adjust or turn off. I turned off everything just to get it to work then dialed them in.

just connected to it and it did say it needed to be updated, downloaded the new software and I am going to try it again.

 

[GuyGoldy41!]

Quick update: you are all awesome!!
The Dc to Dc had the software updated
Dc to Dc also had a setting that wasn’t recognizing the van on (fixed)
Replaced the 400amp fuse with an 80
Added wire support

All is working perfect!