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What happens when CG 110v power fails?

August 28, 2013, 04:27:32 pm

Wise Ones,

Assume for discussion purposes that our 2001 U320 is plugged in at a CG and have one of the AC units on and the 110v Aquahot heater on.  Neither are actually cooling or heating at the time we leave for a trip to the grocery store.  While on our shopping adventure the CG power fails.  What happens to the AC and the Aquahot heater?  I am hoping those circuits are isolated from the inverter powered 110v circuits and that that they will just not operate. 

Am I correct?

Thanks

Roger

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Re: What happens when CG 110v power fails?

Reply #1 – August 28, 2013, 04:36:36 pm

Roger,

Easy to tell-- unplug and see what does/does not work from the inverter. 

You can also look at the inverter-supplied sub-panel to see what is wired to it (suspect that is how yours is wired).

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Re: What happens when CG 110v power fails?

Reply #2 – August 28, 2013, 05:01:47 pm

Yes they should be.  Just look at your boxes. I have two one for the inverter and the other for both the inverter and regular shore power.

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Re: What happens when CG 110v power fails?

Reply #3 – August 28, 2013, 05:18:39 pm

Either turn the inverter off or set the generator on autostart.

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Re: What happens when CG 110v power fails?

Reply #4 – August 28, 2013, 08:08:43 pm

The way it was wired from foretravel would not have any roof ac or aqua hot wired into the inverter circuit.

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Re: What happens when CG 110v power fails?

Reply #5 – August 28, 2013, 09:25:51 pm

Thanks for the feedback.  I was pretty sure that they were independent of the inverter supplied circuits based on looking at the wiring diagrams and breaker boxes as suggested.  I've inadvertently switched off shore power with one or the other still on and haven't seen any problems but have corrected the situation quickly. 

The genset autostart should start the genset if battery voltage gets low, correct?  If it is switched on and the genset is not running and shore power fails, when the AC wants to start or the Aquahot heater wants to turn on will it cause the generator to start? 

I'm not sure if my autostart actually works.  Is there a way to test it without running the battery voltage down?  The inspector who check out our coach before we bought it said it wasn't working.

Thanks

Roger

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Re: What happens when CG 110v power fails?

Reply #6 – August 29, 2013, 09:24:37 am

Many autostart units activate on low battery voltage only. Ours operates on low battery voltage or high cabin temperature. It does not activate on loss of shore power. It does have a thermostat built into it so that it will fire up the generator if the inside temperature exceeds the set point.

Our unit, an aftermarket Magnum AGS, has a "Test" button. If the autostart is working properly, the "Test" button will start a test sequence. It will start the generator, run it for a couple of minutes, then shut it down. 

You might be able to test for low voltage start by putting several loads at the same time on the house batteries. That will cause the voltage to sag temporarily. It might sag enough to kick the autostart. Our autostart engaged when I had it "On" while starting our coach. We normally start with the "Boost" switch on. The voltage sagged enough to trip the autostart. We leave autostart "Off" unless there is a specific reason to turn it "On."

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