generator starter hooked up to coach or chassis battery?

wa8yxm wrote:
I have found my Aux-Start or Emer-Start button (Also known as boost on some RV's) works both ways.. If the house is low, holding it will let the Generator start,, hold till the transfer switch transfers.

That is true. However, the battery boost switch and the generator start button in my RV are about 20 feet apart. You would need long arms to do that. HowSomeEver, if I start the RV's engine, it automatically engages the battery boost solenoid to charge the house battery. That also connects them to let me start the generator off of the chassis battery.

Chris Bryant wrote:
Most RV generators do not charge the battery, they power the converter, which charges the coach battery. That is why the coach battery starts it.

Chris said it, but that said there are a few exceptions, and in a very few cases (Relative) there is a 3rd battery JUST for the generator.

I have found my Aux-Start or Emer-Start button (Also known as boost on some RV's) works both ways.. If the house is low, holding it will let the Generator start,, hold till the transfer switch transfers.

thanks for all the responses.
I will keep the gen's starter connected to the coach battery.
I just did not like the additional fat cable connected from coach battery directly to gen's starter.
trying to simplify now that I am in the solar world... :)

Generally, the generator's starter is connected to the house battery. That way, the vehicle motor and the generator are not on the same battery, so a single dead battery can't kill all starting. If on separate batteries, a dead house battery, you can still start the RV, and a dead chassis battery, you can still start the generator. Both of those options allow battery charging to reclaim the dead battery.

Matt_Colie wrote:
There should be nothing on the main engine (chassis) battery that is not directly related to the main engine.

With the exception of the automatic step. That should also be on the engine battery. That way, even with the house battery disconnected, the step can still retract when the engine is started.

dons2346 wrote:
The OP is asking about how the generator is started, whether from the chassis battery or the house battery and which is the best way.

The question has nothing to do with which battery the generator charges.

No, the OP is asking about why it is hooked up this way- advantages and disadvantages. I thought it was pretty obvious that running the chassis battery dead while running the genset is a disadvantage. I guess it wasn't.

What is YOUR answer?

Coach battery is perfect. If you run the coach out of enough power to start the genny do the following .
Start the coach. Wait a minute. Chassis starts to charge coach batteries and takes over running coach functions. Start genny. Turn off engine. Let genny charge batteries; I contend that if you run the battery down so far that it will not turn over the genny you are ruining your batteries for the coach

Tony,

Yes, it is normal and it is a good idea for both RVs and boats. (Which are also R Vessels.)

There should be nothing on the main engine (chassis) battery that is not directly related to the main engine. The house/hotel (coach) can do what ever you/it wants.
If the house battery goes down, you get dark and maybe cold.
If the main engine battery goes down and you need the engine, that could be a very bad situation.

Most RVs (both types) charge both battery banks with the main engine. So, you have a built-in redundancy.

Before the depression, I did a lot of electrical work on boats. While many smaller boats had a single bank, I was frequently hired to make the system like this after the owner got towed into port.

Matt

Maybe but if the gen were started from the coach battery often enough without that battery being charged it could be a problem if that battery were run down too far. The Chassis battery is usually set apart so that you can always at least start the RV to leave, instead of using it to power any of the other features in the coach. I think others were just explaining the reasoning behind connecting it to the house battery.

The OP is asking about how the generator is started, whether from the chassis battery or the house battery and which is the best way.

The question has nothing to do with which battery the generator charges.

Most generators supply power to the house portion of the motor homes, so they are connected to the house battery as a rule, some also charge the chasis battery when running through a batttery isolator, the generator is used to charge the house battery while running the roof air connditioner, the microwave oven, and any other house hold appliance that requires 120 v a/c electric power while boondocking.

navegator