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Topic: Shore power / generator question (Read 406 times) previous topic - next topic

Shore power / generator question

Last night a big thunderstorm came through our campground (Milton Fl.) with lots of lightning. The power went out several times which required turning off the ACs. What would happen if I started the generator while the shore power was off to run the ACs and then  shore power comes back on? Does the generator still keep the load or does it switch back to shore power? I couldn't go out side to turn off the shore power breaker.
Which source is primary in this case?
Rick & Deborah Webster
2002 3610 U320 #5964
2014 Jeep Wrangler Sahara JKU- 'Copperhead'
Richland Chambers Lake, East Texas

Re: Shore power / generator question

Reply #1
OE is for the generator to be primary-- meaning if the generator is running, it will supply all your 120 VAC. That does not insure that that is how yours is wired if someone replaced the ATS.

Safest when an electrical storm is imminent, DISCONNECT shore power at the pedestal. Some just turn off the CG breaker, but lightening can come down the neutral and ground wires as well.
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: Shore power / generator question

Reply #2
Safest when an electrical storm is imminent, DISCONNECT shore power at the pedestal. Some just turn off the CG breaker, but lightening can come down the neutral and ground wires as well.

Yup, happened to us in Prescott, AZ last year during a "monsoon". Did a CB+ worth of damage. We have a EMS now, but I still follow Brett's suggestion!  ^.^d
1993 U-240 "La Villa Grande"..CAT 3116 w/ Pacbrake PRXB...Allison 3060 6-speed..
Previous: 1983 Airstream 310 turbo diesel, 1979 Airstream 280 turbo diesel
                                      Build # 4297
                                      PNW natives
                      Home base:  'Cactus Hug' (Ajo, Arizona)
                        DW Judy & Chet the wonder dog
                        Full-Timers 'Sailing the asphalt sea'

Re: Shore power / generator question

Reply #3
In many cases EMS's offer a FALSE sense of protection against lightening strikes.

None will thwart a near-by lightening strike. Just too many joules of energy to dissipate.
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: Shore power / generator question

Reply #4
Great information and safety advise. I will test it when we get back home to make sure it is OE operational. Hopefully, storms like that will be few are far between.
thx
Rick & Deborah Webster
2002 3610 U320 #5964
2014 Jeep Wrangler Sahara JKU- 'Copperhead'
Richland Chambers Lake, East Texas

Re: Shore power / generator question

Reply #5
In many cases EMS's offer a FALSE sense of protection against lightening strikes.

AND, if you take a hit and fry the EMS, that is usually not a warranty situation.  :'(
1993 U-240 "La Villa Grande"..CAT 3116 w/ Pacbrake PRXB...Allison 3060 6-speed..
Previous: 1983 Airstream 310 turbo diesel, 1979 Airstream 280 turbo diesel
                                      Build # 4297
                                      PNW natives
                      Home base:  'Cactus Hug' (Ajo, Arizona)
                        DW Judy & Chet the wonder dog
                        Full-Timers 'Sailing the asphalt sea'

Re: Shore power / generator question

Reply #6
Quote
AND, if you take a hit and fry the EMS, that is usually not a warranty  situation
I think we will find that if our Progressive Industries EMS is blown for ANY reason and in ANY time they will replace or repair at no cost to us.
They have great customer service.

Not the same for other EMS manufacturers including the one sold by Camping World.

Re: Shore power / generator question

Reply #7
We used our first EMS unit for several years before it took one hit too many and quit. I shipped it($$$) to Progressive Ind. and I was told it was out of warranty(or too old) and could not be repaired/refurbished. We were without one for several months and I was VERY nervous, so we bought another (SurgeGuard brand,on sale) at a New Store Opening of a Camping World near Spokane, WA.  Fast forward 1 year and 11 mos .... we are in the campground at Buckley AFB in Denver when a sudden and dramatic storm blows through. The sky became dark enough that I was impressed, I shut off the AC units, took the visiting grandkids and went to the laundry room for shelter.  Mr Wonderful stayed in the coach, oblivious to danger. There was a bit of wind, some short burst of rain, and then all the power went out.  ALL the power went out ... the entire base was shut down! At the end of the day, we learned that the sub-station a few miles south of the base had taken a hit from a small tornado!  In the campground, we were one of 2 rigs that had been protected by our surge protection units. Everyone else had blown refrigerators, TVs, computers ... you name it. Our SurgeGuard was fried, by the way.  We went to the local Camping World, they pulled up the almost 2 yr old receipt, and we walked out with a replacement!  I use it religiously. Worth every nickel. 
Carol & Jeff Savournin
Usta have a '93 U225 36', Usta have a '95 U320 40', Usta have a '02 U320 40'
Usta have a 2006 Born Free, Usta have a 2011 Phoenix Cruiser
Usta have a 2012 Jeep Wrangler Unlimited 4dr
"Your time is limited, so don't waste it living someone else's life."  Steve Jobs

Re: Shore power / generator question

Reply #8
I don't know how we skated for so many years (30amp vs. 50amp?), but I'm sure pleased to have a Progressive EMS, especially around "monsoon country"!  ^.^d  Thanks for the responses. M
1993 U-240 "La Villa Grande"..CAT 3116 w/ Pacbrake PRXB...Allison 3060 6-speed..
Previous: 1983 Airstream 310 turbo diesel, 1979 Airstream 280 turbo diesel
                                      Build # 4297
                                      PNW natives
                      Home base:  'Cactus Hug' (Ajo, Arizona)
                        DW Judy & Chet the wonder dog
                        Full-Timers 'Sailing the asphalt sea'

Re: Shore power / generator question

Reply #9
Hi Jeff and Carol,

I have a Progressive EMS and have had it quit. It was repaired free of charge. Now when really severe weather is nearby I unplug from the pedestal, including the cable connections. Better safe than sorry.
Jim Frerichs
2002 U320 42'

Re: Shore power / generator question

Reply #10
I have a Progressive EMS and have had it quit. It was repaired free of charge.
Did it "quit" because of a hit, or?
1993 U-240 "La Villa Grande"..CAT 3116 w/ Pacbrake PRXB...Allison 3060 6-speed..
Previous: 1983 Airstream 310 turbo diesel, 1979 Airstream 280 turbo diesel
                                      Build # 4297
                                      PNW natives
                      Home base:  'Cactus Hug' (Ajo, Arizona)
                        DW Judy & Chet the wonder dog
                        Full-Timers 'Sailing the asphalt sea'