How do these breakers work?

[TTD]

Hmm.... as I wrote the above synopsis, I just realized I did not verify if my chassis batteries are now charging while plugged into electric... will have to do that today! If it's not charging, maybe the chassis ACR button is also tripped! I'll let you know.

UPDATE: Just verified that the CHASSIS ACR button was not tripped - and the Chassis batteries are being charged plugged into electric.

This leads me to believe that if EITHER of the ACR buttons is tripped, that it could cause the original problem.

I didn't want to trip the breaker to test as everything is working great at the moment!

It does make me wonder if I needed the BATTERY BOOST function to work, if that would also not work if either ACR button is tripped? In other words, does either breaker being tripped remove the connection between the two batteries?

[Fredward]

For all those fact checkers following this thread I will add the following detail: On my 2000 Magna and my friend’s 2006 Intrique there is a switch activated by engine oil pressure that closes a normally open relay between the chassis batteries and the house batteries (also the boost relay By The Way) thereby connecting all the batteries together in one big parallel circuit. So when the Cat is running it is charging all the batteries.

I’m not sure what happens when running the generator while going down the road because then the inverter/charger is also charging the house batteries. But I assume the inverter/charger sees that the batteries are adequately charged and just floats.
Fred

[TTD]

Originally Posted by Fredward

there is a switch activated by engine oil pressure that closes a normally open relay between the chassis batteries and the house batteries (also the boost relay By The Way) thereby connecting all the batteries together
Fred

Interesting that yours is determined by oil pressure.

If I understand my system correctly, the BATTERY LINK item that I mentioned earlier in the thread does basically the same thing?

Here is the description the give (they are talking about BOATs, but I assume it's identical in a motorhome with two battery banks):

The CL-Series BatteryLink™ ACR connected into your boat’s electrical system
provides automatic control for charging dual battery banks. The ACR has two
parts:
• A relay - a switch that is activated by an electrically powered magnetic coil.
• An electronic circuit that senses the voltage level of the boat’s batteries
and signals the relay to switch:
- Closed when voltage is high (the ACR’s COMBINE voltage)
- Open when voltage is lower (the ACR’s UNDERVOLTAGE voltage)
When the voltage level of the battery bank being charged reaches a certain level, both battery banks are automatically connected and charged.

[Mr_D]

My '09 Magna also has the oil pressure switch as Fredward describes.

[CountryFit]

I believe all CCs, and other major makes are having the same switch. The oil pressure switch closes the circuit so to charge both batteries. It's a standard design.

When genset is running while engine is running, genset charges house battery through inverter (and 8a dc charge to chassis battery on my coach - not sure all the same but mine does this). They charge batteries concurrently until batteries are full, then float.

[Crop Duster]

On our 2004 Allure, there is an oil pressure switch that closes at 4 psi which closes a relay connecting the coach and chassis batteries. This allows the alternator to charge both sets while driving.

When connected to shore power or when on the generator the inverter charges the coach batteries. The chassis battery is charged through the Echo charger which gets its power from the coach batteries when they get to 13.5 volts I think.

[wsmcycle]

The oil pressure switch does this one simple thing. It indicates the engine is running. If the engine is running, then connect all the batteries. If the engine is not running, don't connect because the house batteries might be low and sick down the chassis battery so that there might not be enough power to start the engine.

[twinboat]

The oil pressure switch closing a relay between the batteries may be an OK system if you have a smaller house battery bank. There will be little chance of overheating the alternator charging them. Many class C MHs use a simple key operated solenoid.

With large 600 +AH house banks, the voltage sensing device will protect the alternator and the chassis voltage, needed to operate the onboard computers.

Once it combines the banks, it monitors the chassis battery voltage. If the voltage drops to low, it disconnects the combined batteries for a time, letting the alt cool down while bringing the chassis battery voltage back up.
It will cycle thru that routine until the house battery voltage raises enough that it doesn't drag down the chassis to much.

[TTD]

That makes sense.... Thank you for clarifying.