Author Topic: Does generator charge house or starting battery?  (Read 2091 times)

Jason Worman

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Does generator charge house or starting battery?
« on: May 18, 2019, 08:16:08 PM »
Hi everybody

I have a basic question, does the generator charge either the house or starting battery while running?

Jason

Bill Lampkin

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Re: Does generator charge house or starting battery?
« Reply #1 on: May 18, 2019, 09:02:36 PM »
Yes, Just like when you are on shore power, your inverter/charger will charge both chassis and house batteries.
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David T. Richelderfer

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Re: Does generator charge house or starting battery?
« Reply #2 on: May 19, 2019, 02:15:29 AM »
In more detail, the generator and shore power supply 120v to the transfer switch.  The transfer switch transfers 110v to the inverter/charger.  The charger unit internal to the inverter converts the 110v to 12+v and sends 12+v power to the house batteries, and that same 12+v power is sent on to the chassis (starter) batteries through the Big Boy/BIRD system after the house batteries have been sufficiently charged.

So... yes, both the generator and shore power will charge both the house and chassis batteries IF the transfer switch, inverter/charger, AND Big Boy/BIRD system are ALL working properly.

From the engine, the engine's alternator sends 12+v to the chassis batteries, and that same 12+v power is sent through the Big Boy/BIRD system after the chassis batteries have been sufficiently charged.

The Big Boy/BIRD system is an important system used to keep both the house and chassis batteries charged.  Note:  Some coaches have an ECHO charger or some similar bi-directional device instead of a Big Boy/BIRD system.

BIRD means Bi-directional Isolator Relay Delay.
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Fred Brooks

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Re: Does generator charge house or starting battery?
« Reply #3 on: May 19, 2019, 02:04:02 PM »
Greetings Jason,
  Your 91 Contessa has a basic charging system that was common for that era. If you look upward on the ceiling of the battery compartment you will find the wiring and components that charge your batteries. The inverter/converter just charges the house batteries. I believe your 91 was before the installation of the Echo Chargers. The device was made by Heart Interface and is still made by Xantrex. Here is how that works: When on shore power or generator the inverter/ converter starts to charge the house batteries. When the echo charger senses the house batteries are above 13.2 volts it then latches onto the chassis batteries and starts to charge them. Most common problem with that device is the inline 20amp fuse going to the chassis battery is blown.
Hope this helps, Blessings & Joy Fred Brooks
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