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Topic: AC Power Anomoly (Read 1045 times) previous topic - next topic

AC Power Anomoly

I parked in dry camp this afternoon, and started my generator for a/c. The a/c units were run on low for approx. 25 min., when they dropped off, the generator made asound like slowing down, and suddenly no AC power at all. Checked all circuit breakers, including those on the Zantrex Freedom Inverter. Nothing appeared out of place. But no AC power anywhere.

Any help would be hugely appreciated!
1989 Foretravel U300 Grand Villa
Build #3410

Re: AC Power Anomoly

Reply #1 –
What is your fuel level?
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: AC Power Anomoly

Reply #2 –
Did you turn off and back on the breakers on the generator itself?

And, what generator do you have?

Any problem with re-starting the generator?  Run OK?

If generator is running OK, next step would be to check connections from generator to house and then at the ATS.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: AC Power Anomoly

Reply #3 –
Brett, thanks.

1. Generator is Cummins Onan 7.5;

2. Gen ran fine throughout incident. I have started the genset a number of times, and it seems to run fine.

3. I can only find one pop-out type 25 amp breaker on the main face of the generator, and none in the main fuse/breaker box.

I checked all visible electrical connections between genset and inverter—there really are no visible connections—just many boxes with heavy AC wiring.
1989 Foretravel U300 Grand Villa
Build #3410

Re: AC Power Anomoly

Reply #4 –
First turn any breakers that you find on and off a few times.  Cannot always tell if tripped unless you do that.  Next take off cover on ATS and check for voltage on the contactor terminals.  With an INSULATED screwdriver you can manually push a contactor in but first disconnect all 120 volt supply and turn off the inverter.  Obviously have the genny running.  Be careful if you are not comfortable with electricity don't do it.

Keith
Keith, Joyce & Smokey the Australian Cattle Dog
1995 U320 SE Extreme 40' WTBI Build # 4780, with a Honda CR-V hopefully still following behind.
Motorcade # 17030
FMCA # F422159

Re: AC Power Anomoly

Reply #5 –
The power wires for the air conditioner do not run through the inverter.
Do you have an ATS switch on your model coach?
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: AC Power Anomoly

Reply #6 –
1st, turn everything off. This happened to me on my 88.... if memory serves me 200A in line breaker

In big bay to the rear of the gen set should be your electrical connections. Behind the wall they are mounted on is a round access hole. You can reach it from the smaller compartment near the water bay. In this access hole is the main reset, just push it in, you will hear the click.

Start everything up
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My advice and experiences are Free, you decide if they are worth anything .

John - driving Old Faithful
1994 U280 GV
C8.3, Banks, Pacbrake, 900 watts, Resonator, XLHD tow dolly
Retired Army Warrant Officer

Life is what you make of it - if it is lemons, make lemonade!
Former Coaches:
1988 GV 40' ORED 300HP CAT - 9 years
1990 Winnebago LeSharo - 3 years
2000 Newmar London Aire - 3 years (#18 of 23 produced)

Re: AC Power Anomoly

Reply #7 –
Is your generator the same as this?
I had to replace the circuit breaker on mine it had gotten tired and lost continuity through it.
91 GV U300 Unihome 40' Build 3811
6V92TA Detroit

Re: AC Power Anomoly

Reply #8 –
Stump,

Yes—Identical generator. Starts and runs fine, but no electrical output, and the only circuit breakers I can find are the two main box 50a breakers. None on the generator itself.
1989 Foretravel U300 Grand Villa
Build #3410

Re: AC Power Anomoly

Reply #9 –
See the middle picture Mine has a breaker there.
91 GV U300 Unihome 40' Build 3811
6V92TA Detroit

Re: AC Power Anomoly

Reply #10 –
OK, the picture solved the mystery. On mine, the clearance is tight on the front, ad I couldn't see the breaker due tight dark area and wire obscuring.

The breaker is tripped (outboard) and will not remain closed upon gen start.
1989 Foretravel U300 Grand Villa
Build #3410

Re: AC Power Anomoly

Reply #11 –
With the one breaker tripping as soon as it "makes power" there are a couple of things to check.

There could be a bad connection/dead short at the generator to coach wiring, in the coach wiring to the ATS (not very likely) and at the ATS-- generator "IN" side.

I would start with those. few connection areas.

Yes, it could also be in the generator, in which case, if you disconnect generator to coach wiring it would still trip.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: AC Power Anomoly

Reply #12 –
Great Brett, thanks again. This gives some specific things to run down and I'm sure I can find the ground and have already located the connections for the ATS.
1989 Foretravel U300 Grand Villa
Build #3410

Re: AC Power Anomoly

Reply #13 –
When you reset it does it click back in nice and firm or feel mushy? Mine felt mushy, replaced it no more issues.
91 GV U300 Unihome 40' Build 3811
6V92TA Detroit

Re: AC Power Anomoly

Reply #14 –
Quote from: RandallBrink –
OK, the picture solved the mystery. On mine, the clearance is tight on the front, ad I couldn't see the breaker due tight dark area and wire obscuring.

The breaker is tripped (outboard) and will not remain closed upon gen start.
Is everything turned off inside,A/C etc?
Turn off all 120v breakers inside coach. Reset the breaker on the generator. Start Generator . Does breaker trip? Yes/No
 If No go inside coach and start turning on breakers see which one circuit is causing fault.
91 GV U300 Unihome 40' Build 3811
6V92TA Detroit

Re: AC Power Anomoly

Reply #15 –
My recollection is that was mushy, not the firm snap you'd expect.
1989 Foretravel U300 Grand Villa
Build #3410

Re: AC Power Anomoly

Reply #16 –
I will do this test. When I was testing yesterday, I was not turning off the 120v breakers. Should have remembered to do this.
1989 Foretravel U300 Grand Villa
Build #3410

Re: AC Power Anomoly

Reply #17 –
What did you find?
91 GV U300 Unihome 40' Build 3811
6V92TA Detroit
 

Re: AC Power Anomoly

Reply #18 –
I have not yet had the opportunity to go through the breaker test, but plan to do so tomorrow, Wednesday, Aug. 29th. Thanks, and will report findings.
1989 Foretravel U300 Grand Villa
Build #3410