Chassis battery charging

[Trkyte@msn.com]

As I was sitting here under house arrest, I was thinking about previous posts with dead chassis batteries
On our class c’s we usually have a time delay isolation relay and not a bird.
This means the chassis battery is only charged with the engine. I’ve read where some of us use a maintainer, plugged into the power port when on shore power.

If I were to replace the momentary emergency start switch with a latch style switch. I could then charge both chassis and coach batteries when on shore power. Yes , it’s something you have to remember when off of shore power but sometimes I’m on shore for weeks on end.

So, let’s hear some opinions and maybe shoot a hole in my theory.

[cavie]

Your chassis battery should have no problem sitting for weeks on end. My wife's car sits in the garage for months on end. Just put a maintainer on it if it bothers you.

[EA37TS]

Originally Posted by Trkyte@msn.com

As I was sitting here under house arrest, I was thinking about previous posts with dead chassis batteries
On our class c’s we usually have a time delay isolation relay and not a bird.
This means the chassis battery is only charged with the engine. I’ve read where some of us use a maintainer, plugged into the power port when on shore power.

If I were to replace the momentary emergency start switch with a latch style switch. I could then charge both chassis and coach batteries when on shore power. Yes , it’s something you have to remember when off of shore power but sometimes I’m on shore for weeks on end.

So, let’s hear some opinions and maybe shoot a hole in my theory.

What makes you think the chassis battery is not charged off shore power and that you don’t have a BIRD? My prior class c had a bird.

[Down South]

I was thinking that the chassis battery did charge when hooked to shore power. Have you checked the voltage of the chassis battery while on shore power? If the battery is being charged while on shore power the voltage will be above 13 volts.

[bry899]

Originally Posted by Trkyte@msn.com

As I was sitting here under house arrest, I was thinking about previous posts with dead chassis batteries
On our class c’s we usually have a time delay isolation relay and not a bird.
This means the chassis battery is only charged with the engine. I’ve read where some of us use a maintainer, plugged into the power port when on shore power.

If I were to replace the momentary emergency start switch with a latch style switch. I could then charge both chassis and coach batteries when on shore power. Yes , it’s something you have to remember when off of shore power but sometimes I’m on shore for weeks on end.

So, let’s hear some opinions and maybe shoot a hole in my theory.

I have a 2018 Four winds 22E (Class C) the chassis battery is only charged by the engine.
I added a Trik L Start:
Mega TRIK-L-START Starting Battery Charger/Maintainer
Charges the chassis battery from shore power, Generator power, or solar power.
$55 + $8 shipping, and I installed it in 20 minutes

[coachray]

I have a 2019 class c Quantum RQ29 and my chassis battery is only charged by the engine. During the winter I'm plugged into shore power in my driveway, and I periodically start the engine and put engine battery on a charger when needed to keep it maintained.

[bry899]

Originally Posted by coachray

I have a 2019 class c Quantum RQ29 and my chassis battery is only charged by the engine. During the winter I'm plugged into shore power in my driveway, and I periodically start the engine and put engine battery on a charger when needed to keep it maintained.

Once the Trik L Start is permanently installed, the chassis battery gets charged from shore power, generator power or solar power.
no need to hook up any other chargers or run any other power cords.

[coachray]

Originally Posted by bry899

Once the Trik L Start is permanently installed, the chassis battery gets charged from shore power, generator power or solar power.
no need to hook up any other chargers or run any other power cords.

Just now looked at the Trik L Start and I like it. My question is do you hook it up to only one of the house batteries?

[bry899]

Originally Posted by coachray

Just now looked at the Trik L Start and I like it. My question is do you hook it up to only one of the house batteries?

http://www.lslproducts.net/MTLS_Instructs.pdf

The pdf instructions explain further.

I mounted it on the inside (drivers side) fenderwall, the unit has 3 wires,
the instructions explain which wires to attach 1st, 2nd, 3rd

1 wire is for the ground.
1 wire is for the chassis battery and is attached to the battery isolator terminal for chassis battery.
1 wire is for the coach battery bank and is attached to the battery isolator terminal for coach battery bank.

My battery isolator is on the firewall, see the instruction pdf for images

[bry899]

the isolator (roundish) nest to the isolator relay delay box
the trik l start is the box on the bottom right of the first picture, sorry I couldn't figure how to turn the image.




It is tight in there and I had to unbolt the radiator overflow container (or whatever it is called)

[JimOIB]

It seems that how chassis and coach batteries charge is dependent on the type of class c. My2017 24F has a battery isolation manager - BIM160.


https://precisioncircuitsinc.com/pro...ion-manager-2/

It states - The Battery Isolation Manager goes between the Chassis and Coach Batteries to maintain both batteries when either one is charging.

I guess there is a subtle difference between charging and maintaining.

[Judge]

Originally Posted by jimbo12

It seems that how chassis and coach batteries charge is dependent on the type of class c. My2017 24F has a battery isolation manager - BIM160.


https://precisioncircuitsinc.com/pro...ion-manager-2/

It states - The Battery Isolation Manager goes between the Chassis and Coach Batteries to maintain both batteries when either one is charging.

I guess there is a subtle difference between charging and maintaining.

I have done some troubleshooting and research on the BIM160/BIM225 Battery Isolation Manager for my 2020 Magnitude SV34 and learned several things:

- It is an intelligent monitoring system. The microprocessor looks for certain conditions to determine the appropriate operation mode.

- It does keep the house batteries and chassis batteries isolated so the coach cannot drain the engine starting (chassis batteries).

- It provides the ability for an Emergency Start Switch so the house batteries can provide a boost to the chassis battery if it becomes drained and cannot start the engine on its own.

- When the engine is not running and the coach is on shore power, it will enable the internal relay to connect the house batteries and their charger to the chassis battery IF the chassis battery voltage drops below 12.6V and the house batteries already have a sufficient charge in order to charge the chassis battery when the engine is not running.

- When the engine is running and the coach is not on shore power, it will enable the internal relay to connect the chassis battery and alternator to the house batteries IF the house battery voltage drops below 12.6V and the chassis battery already have a sufficient charge in order to charge the house batteries when not on shore power.

- According to the manufacturer of the BIM160/225, it does not matter if the chassis battery is connected to the BATT-A post or the BATT-B post on the BIM160/225. I found this not to be the case.... at least on my coach. I was having issues with the engine alternator keeping the house batteries charged when driving with the Inverter on for the fridge. I found that other motorhome manufacturers using the BIM160/225 all wired the chassis batter to the BATT-A post on the BIM while Thor wired the house batteries to the BATT-A post and they connected the chassis battery to the BATT-B post. After I swapped the cables on the BATT-A and BATT-B posts, the BIM started working as I expected. It would engage the relay when the house batteries dropped below 12.6V while driving and I can now hear the relay engage when I am on shore power and the chassis battery drops below 12.6V, which I never heard it engage before when I was on shore power and the chassis battery was below 12.6V.


I installed the Trik-L-Start on my last motorhome (a 2018 Outlaw 29H Class C) so the house batteries could maintain the chassis battery since it did not have a Battery Isolation Manager and it did a good job keeping thew chassis battery maintained. Now that I see how the BIM160 works on my Super C, I might have installed one on my old Class C if I had known about it then..... but the Trik-L-Start was easy to install and is less expensive.

[Trkyte@msn.com]

Fixed it.....

I was going to add a maintainer to the chassis battery like the previous post, but then I realized I had a simple solution.

I previously added another power port tapped off the rear of the radio to supply a SiriusXM receiver from the coach batteries when camping. Since then I replace the pos factory radio with one that has SiriusXM built in.

For ten bucks I bought two plugs and tied them together as shown.

Now when on shore power both batteries are maintained.

[16ACE27]

Originally Posted by Trkyte@msn.com

Fixed it.....

I was going to add a maintainer to the chassis battery like the previous post, but then I realized I had a simple solution.

I previously added another power port tapped off the rear of the radio to supply a SiriusXM receiver from the coach batteries when camping. Since then I replace the pos factory radio with one that has SiriusXM built in.

For ten bucks I bought two plugs and tied them together as shown.

Now when on shore power both batteries are maintained.

I'm thinking a dead chassis battery will smoke that wiring pretty quickly.

And leaving your lights on without being plugged in will kill all the batteries.

[bry899]

Originally Posted by Trkyte@msn.com

Fixed it.....

I was going to add a maintainer to the chassis battery like the previous post, but then I realized I had a simple solution.

I previously added another power port tapped off the rear of the radio to supply a SiriusXM receiver from the coach batteries when camping. Since then I replace the pos factory radio with one that has SiriusXM built in.

For ten bucks I bought two plugs and tied them together as shown.

Now when on shore power both batteries are maintained.

You basically added the Chassis battery to the coach batteries in parallel, with no protection.

[Trkyte@msn.com]

Both power ports are fused. The coach battery is fused with a fifteen amp. It would blow before anything else.