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Topic: Run Generator While on 30 Amp Shore Power (Read 1118 times) previous topic - next topic

Run Generator While on 30 Amp Shore Power

Too hot for one a/c here in Arizona. Can I remain on 30 amp shore power but start generator so I can run both a/c until it cools this evening?

Thanks
Randy (N4TDT) and Karen Crete
Sarasota, Florida
SOLD:  2000 U270 34' WTFE Build 5756 "Ole Red"

Re: Run Generator While on 30 Amp Shore Power

Reply #1 –
When you're on generator the transfer switch will switch you over once you shut generator off it'll go back to 30 amp hour
2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago

Re: Run Generator While on 30 Amp Shore Power

Reply #2 –
Quote from: floridarandy –
Too hot for one a/c here in Arizona. Can I remain on 30 amp shore power but start generator somI can run both a/c until it cools this evening?

Thanks
Randy, if I'm not mistaken when you startle generator the transfer switch will put everything on the generator and isolate shore power
Isolate--meaning it does not use shore power
I killed a transfer switch in another brand by starting generator while on shore power,  transfer was suppose to be automatic but it wasn't
Personally I would un-plug shore power then start generator so both AC units could run.  Then once cooled off I would switch back to shore power with 1 AC
Chris
1999 U 320 DGFE
Build Number 5523
Chris & Elka Lang
In the field, Lonoke AR

Re: Run Generator While on 30 Amp Shore Power

Reply #3 –
Quote from: Chris m lang –
Personally I would un-plug shore power then start generator so both AC units could run.  Then once cooled off I would switch back to shore power with 1 AC
X2, except no need to unplug.  Just flip the appropriate breakers off and on at the power pedestal (or box).  Have the air conditioners turned off when making the switch between power sources to reduce the strain on the ATS.
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Run Generator While on 30 Amp Shore Power

Reply #4 –
Like Chuck says, turn off ALL power users when switching over to the generator. These motors do not like slow voltage starts and ultimately go bad.
My Owner's manual stresses shutting everything off when switching, and they stress it more than once.
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: Run Generator While on 30 Amp Shore Power

Reply #5 –
94-02 had shoreline priority.  Others had generator priority.  I have owned one of each.
Steve DeLange
2005 U320T 40'
Pearland, Texas

Re: Run Generator While on 30 Amp Shore Power

Reply #6 –
My '99 U320 has shoreline priority.  Is there a way to easily change this to generator priority?
Forest & Cindy Olivier
1987 log cabin
2011 Roadtrek C210P
no longer 1999 36' U320 build #5522
2013 Rzr 570 & 2018 Ranger XP1000
2006 Lexus GX470
2011 Tahoe LT 4x4
Previous 1998 45' 2 slide Newell, 1993 39' Newell

Re: Run Generator While on 30 Amp Shore Power

Reply #7 –
Quote from: folivier –
My '99 U320 has shoreline priority.  Is there a way to easily change this to generator priority?
I think you could just reverse the position of the input cables going into the ATS box.  Make sure all AC power is cut to the coach before messing with the ATS.  Should be a wiring diagram on the underside of the ATS box cover indicating which breaker connection has priority?
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Run Generator While on 30 Amp Shore Power

Reply #8 –
Quote from: folivier –
My '99 U320 has shoreline priority.  Is there a way to easily change this to generator priority?
Why would generator priority be more advantageous, or vise-versa?
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: Run Generator While on 30 Amp Shore Power

Reply #9 –
Randy,

Best practices:

Turn off all high loads such as A/C's.

Disconnect from shore power or turn off CG breaker.

Start generator and allow a few minutes for it to switch AND warm up.

Turn on heavy loads one at a time.

Can you just go from running heavy loads on shore power to starting the generator and switch heavy loads to it-- sure.  But that is hard on both the ATS and the generator.  Think of it as similar to starting your car and immediately flooring the throttle to 80 MPH.  Yes, it can be done, but hardly "best practices".
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: Run Generator While on 30 Amp Shore Power

Reply #10 –
Quote from: jcus –
Why would generator priority be more advantageous, or vise-versa?
I don't know...good question.  Might have something to do with generator auto-start function?  If (whatever) conditions cause the generator to start automatically, then I guess you would want IT to have priority at the ATS.

I replaced the AC power selection ATS with a manual switch, so I decide what has priority.  Quiet, and simple = good.
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Run Generator While on 30 Amp Shore Power

Reply #11 –
My coach has a manual transfer switch as well. Also has a Victron multicontrol that I can set how much current it draws, from 0-50 amps of either shore power or genset power.
More work, as you have to go in to the bed room to switch it out, but that leaves little room for error. I believe its a blue sea systems 50 amp transfer switch, so very robust. Not much to go wrong with it.
Randy what sized generator do you have?
Also you should be able to run both A/Cs off 30 amps I would think. If not maybe you needa  start capacitor on them.
I can run my rear A/C off shore and front off the lithium bank with the solar charging it. Doesn't power the entire load, but most.  Pretty cool feature. Wouldn't do it often though.  8)
Bob
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired

Re: Run Generator While on 30 Amp Shore Power

Reply #12 –
We're at a 30-amp park now, easy to run the rear air, but with our electric convection oven on at the same time, it takes us down to 110 volts, any lower is dangerous. So, if not started at the same time, I suppose the front air could be run (without the oven), but we've been in some hot temps down south and have never needed the front, only a small fan to circulate the rear air up front.  ^.^d  BTW, 'auto-matic' gen set starting (which we don't have and only run the gen-set in emergencies) is hard on the peace & quiet for the neighbors, which is why we follow this rule:
1993 U-240 "La Villa Grande"..CAT 3116 w/ Pacbrake PRXB...Allison 3060 6-speed..
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