Electrical?

[J-Rooster]

I’m currently camping at the Palm Springs, Joshua Tree KOA. The power went out purposely today for 4 hours. There were workers, working on the underground power lines. My question is can I run my gen set without electricity back feeding into the lines where the workers are working. The temperature was 84* at 10 A.M. and I wanted to use my AC, but wasn’t sure if the electricity could feed back to them are not? Is there a switch in my RV that stops electricity from feeding back or do I have to turn the 50 amp breaker switch off?

[tropical36]

I'm still waiting to hear of a case, whereas an RV genset was trying to parallel itself with the power company. Trying to do so at random and maybe with being 180 degrees out of phase, would probably cause it to remove itself from it's mounting ...lol. Nope, don't think it's gonna happen, folks.
At the same time, I wouldn't want to trust these workers for wiring up something wrong, so would probably go ahead and disconnect, until I was sure.

[J-Rooster]

ArchHoagland wrote:
Unplug from shore power. Do not connect again until you have checked the voltages at the pedestal or several neighbors have plugged in with no problems.

OK, Arch!

[ArchHoagland]

Unplug from shore power. Do not connect again until you have checked the voltages at the pedestal or several neighbors have plugged in with no problems.

[10forty2]

I'm another that always unplugs from shore power BEFORE starting the genset. Just no sense in taking that chance. Best case, you trip a breaker. Worst case, you ruin a generator and/or some circuitry inside the RV or cause an electrical fire. Nobody wants that!

[fourmat]

gbopp wrote:
I'm probably overly cautious. Before I start my generator, I unplug from shore power.
I know the transfer switch will prevent backfeeding or shore power from entering my electrical system. But, I chose to be extra careful.

+1 I just always do that

[LVJ58]

gbopp wrote:
I'm probably overly cautious. Before I start my generator, I unplug from shore power.
I know the transfer switch will prevent backfeeding or shore power from entering my electrical system. But, I chose to be extra careful.

I agree that's the best action to take should transfer switch malfunction.

Good Luck and Safe travels....

[ScottG]

OB thanks for the insight.
I have seen a gen (7kw) hooked up directly to the downed grid. The gen will simply labor down hard while it's trying to power everything in the neighborhood. Nothing is going to get all the way back to the source.
So you'll know rather quickly of you're backfeeding.

[Old-Biscuit]

DrewE wrote:
The transfer switch will prevent backfeed. It's designed and (UL) listed to perform that specific function. That is the primary safety requirement for a transfer switch--that the two sources never be connected to each other. They are designed so that, should they fail, it would be in a safe manner.

It's equally as bad to have the transfer switch connect the generator to the line when the line is live, as the two would almost always not be in phase with each other and the line would drive the generator and vice-versa, quite likely resulting in physical damage to the generator. There are stories of the rotors of the giant generators in power plants being ejected from the power plant building when they mistakenly get connected to the grid out of phase; the same could easily happen to an RV generator. (There could also be pretty bad things happening if the generator were not running at the time; the generator would act like an electric motor, and accelerate the mechanical parts of the generator to running speed mighty quickly, possibly breaking stuff.)



That said, there's nothing wrong with unplugging the cord either, and doing so is an absolute guarantee that you cannot backfeed the campground electrical system.

Worked as a Control Operator in Power Plants.....I was the one that sync'd main gen to grid & I can tell you HOGWASH

Main sync scope has a very narrow window and speed tolerance to allow closing of main gen switchyard breaker.
5* before and 5* after....at max of 3605 rpms

Try to sync outside those parameters and CB will not close

Gen rotors HAVE come apart and gone thru the 6" shell due to internal shorts and explosion of the hydrogen gas used for cooling.

[PastorCharlie]

If it can it will. Murphy law.

[DrewE]

The transfer switch will prevent backfeed. It's designed and (UL) listed to perform that specific function. That is the primary safety requirement for a transfer switch--that the two sources never be connected to each other. They are designed so that, should they fail, it would be in a safe manner.

It's equally as bad to have the transfer switch connect the generator to the line when the line is live, as the two would almost always not be in phase with each other and the line would drive the generator and vice-versa, quite likely resulting in physical damage to the generator. There are stories of the rotors of the giant generators in power plants being ejected from the power plant building when they mistakenly get connected to the grid out of phase; the same could easily happen to an RV generator. (There could also be pretty bad things happening if the generator were not running at the time; the generator would act like an electric motor, and accelerate the mechanical parts of the generator to running speed mighty quickly, possibly breaking stuff.)

That said, there's nothing wrong with unplugging the cord either, and doing so is an absolute guarantee that you cannot backfeed the campground electrical system.

[MrWizard]

unplug from shore power

then start the generator

NO accidental back feed, when the shore cord is unplugged

[gbopp]

I'm probably overly cautious. Before I start my generator, I unplug from shore power.
I know the transfer switch will prevent backfeeding or shore power from entering my electrical system. But, I chose to be extra careful.

[pianotuna]

Hi,

Slightly safer to simply unplug from the pedestal.

Plug a light into the pedestal to let you know when power returns.

[J-Rooster]

Thanks guys for your quick response and explaining to me about the switch! I’m sure the switch is working but I’ll shut the 50 amp breaker off just to make sure. The power is going off again for 4 hours tomorrow!