Chassis battery charge from converter

[craigav]

The larger module is similar on mine and is an 80A breaker for the charge line to the coach battery, the smaller lego looking blocks are auto reset breaker.

Your setup is a lot different looking than mine, at least by the location of everything although the schematic may be similar, just that everything is located differently. I suggest your best bet is to see if you can get a schematic.

I will add an FYI, for those with Class C's there is a common complaint that the chassis battery will run down completely in just a couple of weeks if it isn't kept charged. This is much sooner than it should be absent of any drains on the battery. Some RVrs have simply added a weather proof marine charger installed and connected permanently in order to charge the chassis battery whenever there is shore power. I have also considered doing this as well, in fact I have a waterproof marine charger (5A) that I have used at times instead of jumpering the relay. Seems to work well so I may hardwire the charger in place. I just haven't had time to give my plans a deeper thought lately but plan to do so soon.

More information: Jayco installs a "Diode Adapter" under the dash that is supposed to allow the radio, LP detector, fridge, and maybe something else, to be powered by the coach or chassis battery. These items are supposed to work even if the coach battery is mia, and then use the coach battery when it is available. I suspect that the diode setup is related to why many (maybe most, maybe every one of them???) Class C owners have an issue with the chassis battery staying charged and I highly suspect that Jayco uses a similar setup on the Class A's that have this same issue. What I suspect is that the diode harness may be wired backwards (or in some other improper manner) and favoring the chassis battery instead of the coach battery for those items I listed above.

Another option for you is to install a BIM in place of your aux start relay. That would be an option for Class C owners as well. I am holding off on that idea myself though as I purchased a DC2DC charger quite a while back and plan to install it maybe this winter, when I do I will have to make some changes with the solenoid setup anyway. ~CA

[Kevin Cooper]

Craig, The uncovered terminals on the right, the one on the right has one conductor connected and another one that looks like it broke off. I think the broken one was for the lights in the cab. The RV tech, moved the lights to a different wire inside the dash to fix the issue, not seeing the broken connector. The other wire on that stud is the one that has the .25 amp draw. Once I get it to where I can charge the battery while on shore power, I can start looking for the paracidic draw in the dash. My breaker should be here tomorrow.
I will send request for schematic to Jayco.
Thanks!

[craigav]

As a simple test that you could do when you are working on it next is that you could disconnect that one wire and see what no longer works. In particular check the lp/co detector, radio, and the fridge. Maybe everything continues to work just fine and there becomes a .25a draw increase on the coach battery. (in the case of the diode concerns I mentioned earlier). ~CA

[Kevin Cooper]

I just got the circuit breaker installed on the solenoid used to jump start the RV. House battery was 13.1v chassis was 11.66v. Closed breaker and 6.56 amps flowing to chassis battery. Avoided buying a battery charger and another cord with $10.31 breaker.

[Alante31V]

Sounds like you store RV at home?

Per FORETM;

https://www.precisioncircuitsinc.com...ger-Rev7-1.pdf


https://www.jaycoowners.com/forums/f...r-76068-3.html

[Kevin Cooper]

Originally Posted by Alante31V

Sounds like you store RV at home?

Per FORETM;

https://www.precisioncircuitsinc.com...ger-Rev7-1.pdf


https://www.jaycoowners.com/forums/f...r-76068-3.html

It is hard to get it to fit on 3 acres, but I got a place for it.

[Alante31V]

Originally Posted by Kevin Cooper

It is hard to get it to fit on 3 acres, but I got a place for it.

Lol. I wish I could. Shelling out $85 a month for storage site.

So, not an electrician but, will that properly charge batteries? Not overcharge?

[Kevin Cooper]

Originally Posted by Alante31V

Lol. I wish I could. Shelling out $85 a month for storage site.

So, not an electrician but, will that properly charge batteries? Not overcharge?

The converter in the Alante is a very good battery charger. So, it has the needed 4 stages of charging batteries. No, it will not overcharge them or damage them.
When I’m going to unplug the RV, I will turn off the breaker first. It will only be on when I’m plugged in.

[Foretm]

Pretty late to the party, apologies... My only concern was that in my coach if I jump the coach and house batteries using the "battery boost" switch, it energizes the ignition which triggers the safety on the jacks to auto retract. That's if I hit the battery boost button on the dash, if you wired it differently and that is not an issue for you, then awesome.

I installed the amp-l-start years ago and its been rock-solid ever since. They don't make them anymore, but any BIM with proper ratings would work.

[Kevin Cooper]

Originally Posted by Foretm

Pretty late to the party, apologies... My only concern was that in my coach if I jump the coach and house batteries using the "battery boost" switch, it energizes the ignition which triggers the safety on the jacks to auto retract. That's if I hit the battery boost button on the dash, if you wired it differently and that is not an issue for you, then awesome.

I installed the amp-l-start years ago and its been rock-solid ever since. They don't make them anymore, but any BIM with proper ratings would work.

I’m pretty sure from the information from Craig, that what I did does not do what the button does. At least the steps did not go in like it does with the button, which was my test.
Hopefully, I am avoiding the batteries going dead and destroying them.

[Foretm]

Sounds good... Here's the link to my installation of the Amp-l-start and attached my 12V battery schematic from Jayco. Hope it helps.

https://www.jaycoowners.com/forums/f...ml#post1005851

[Kevin Cooper]

Originally Posted by Foretm

Sounds good... Here's the link to my installation of the Amp-l-start and attached my 12V battery schematic from Jayco. Hope it helps.

https://www.jaycoowners.com/forums/f...ml#post1005851

Thanks very much for the diagram. So, I jumpered between the 4ga red chassis and the 4ga bulk house battery studs. I used #10 copper and a 30 amp circuit breaker/disconnect. This way totally avoids the control wires.
It could also be done with another solenoid, #4 cu wires, and a control wire running up to the drivers area. I’m more into the KISS method though.

[Foretm]

Yea, that's basically what the amp-l-start is doing. The only difference is the voltage sensing on both sides that determines if it should connect or not. I see no issue with it.

[craigav]

I didn't reply back earlier, but I did give it more thought and determined that my plan with using another switch mounted next to the Aux Switch actually will work as I want it to do long as it is a double pole double throw (dpdt) which can be wired to prevent the backflow of power when the switch is on. So one direction enables the Aux Start switch and the other direction disables it and engages the relay (solenoid). ~CA

But I also think a small marine charger (or similar) hardwired is also a great option or like what Kevin did. Just be sure to disconnect the breaker\switch when not on shore power.

[Kevin Cooper]

Craig, How would the orange and the three purple wires be connected in the switch? The one purple wire is going to or coming from the relay. Mine has that relay next to the battery and solenoid. You are more into controls than I am.

[Kevin Cooper]

Originally Posted by Foretm

Yea, that's basically what the amp-l-start is doing. The only difference is the voltage sensing on both sides that determines if it should connect or not. I see no issue with it.

That is similar to what was built into the Thor we had. It was all contained inside a 6x6x4” metal box under the hood. 13.2 volts was its trigger voltage.

[craigav]

Originally Posted by Kevin Cooper

Craig, How would the orange and the three purple wires be connected in the switch? The one purple wire is going to or coming from the relay. Mine has that relay next to the battery and solenoid. You are more into controls than I am.

The Class C setups are likely very similar but not enough so for me to answer your question. There are no purple wires on my setup (actually there could be at the switch but the schematic doesn't show them). Were you able to obtain a schematic for yours?

With a dpdt I would be able to send a power on (12v) signal to the solenoid and at the same time disconnect the 12v power going from the solenoid back to the Aux Start switch that would occur with the Key on or the Aux Start switch pushed and causes the steps to think the key is on along with other things.

I could draw it in on my schematic and share that with you, but it would be best to have a schematic that matches your setup.

~CA

[Kevin Cooper]

Craig, no need to draw it, I understand what you are saying and can see how it would work. Did you see the diagram from Foretm? It helped me understand the controls a little better. And can see how your switch would work.
Have a wonderful evening!

[craigav]

Originally Posted by Kevin Cooper

Craig, no need to draw it, I understand what you are saying and can see how it would work. Did you see the diagram from Foretm? It helped me understand the controls a little better. And can see how your switch would work.
Have a wonderful evening!

I hadn't seen Foretm's diagram until just now. Here is a snippet of my setup in regards to the Aux Start and Solenoid. What his diagram shows as the "AUX SWITCH" is the solenoid and I see the purple wires you mentioned. Mine only shows one Orange wire where there are 4 on your (or in the diagram) and I have a Yellow wire attached to the Aux Start Switch that likely goes to the same places your purple wires go. If I go with the dpdt switch plan, I would have the Yellow wire open and apply power to the Orange to trigger the solenoid.

I am just thinking that I may would do this. I am thinking that a better plan for my setup may be to hardwire a separate charger as I have LifePo4 batteries for the coach and I plan to install a new converter that will charge the LifePo4 at a higher voltage than what I have now, and in doing that I wouldn't really want the higher voltage going to the chassis' lead acid battery, at least not for any extended period of time. If not for the LifePo4's though, I wouldn't be concerned and would likely go with the switch. ~CA

[Kevin Cooper]

You would not want to have a Lifepo charging voltage at around 14.8 volts. Even though the float voltage drops down to between 13.2 and 13.8, you can’t control it.
Please let me know later when you do something, what you did and how well it works.