Exercise Generator On Shore Power

[RetiredAndFree]

When I exercise my generator, do I need to disconnect from my 30 amp shore power? I have been unplugging it before starting the generator off the battery.. I have a 2020 Greyhawk Prestige 30XP. Got it in July and run it once a month for about an hour. I know most say run it for 2 hours but I wonder if 2 hours is necessary.

[cherv]

I always unplug shore power

[Atlee]

My Onan manual says to exercise it 2 hours.

Originally Posted by RetiredAndFree

When I exercise my generator, do I need to disconnect from my 30 amp shore power? I have been unplugging it before starting the generator off the battery.. I have a 2020 Greyhawk Prestige 30XP. Got it in July and run it once a month for about an hour. I know most say run it for 2 hours but I wonder if 2 hours is necessary.

[Pfflyer]

I unplug mine. It takes maybe a total of 2 seconds with my setup.

[RetiredAndFree]

Thanks for the replies. I will keep unplugging and run 2 hours. Tough to run 2 hours here in Michigan today under load. Supposed to be 65 to 70 degrees today. Not warm enough for the AC and if its colder I put a 1500 watt heater inside and let it run. Guess maybe I'll alternate back and forth with them. Thanks again.

[EA37TS]

I leave my shore power plugged in but I trip the 110 breaker in the box.

[Rustynuts]

No need to unplug if you have an automatic transfer switch, this automatically cuts shore power and connects to generator power and back to shore when you turn the generator off.

[RetiredAndFree]

This might be a silly question but how do I know if I have an ATS? Not real electrically savvy here.

[Bobby B]

Like Rustynuts said. No need to in plug. Unless you have a really old Motorhome, it has an ATS.

[edatlanta]

Originally Posted by EA37TS

I leave my shore power plugged in but I trip the 110 breaker in the box.

X2

[Florida Ranger]

Automatic transfer switches can and will fail after awhile when shore power is hooked up , and you fire up the generator. If you ask around you will find that some people who’s switches failed was due to not disconnecting shore power. In my book why take a chance, it’s a personal choice.

[RetiredAndFree]

Like many issues, seems to be many opinions. I will just play it safe and unplug before starting the generator. Just can't go wrong that way. Thanks for all the responses.

[JimD]

No need to unplug as the transfer switch will isolate it from the shore power feed. I never unplug for this operation plus I only exercise for an hour. I know it says to run for 2 hours at about half power but I have always only done an hour at a higher power level (2 ACs). Does that make me a rebel?

I believe the need to exercise the generator is to keep the fuel fresh plus burn off any moisture that may have accumulated. In my opinion, which means little, an hour should get it hot enough and burn enough fuel to get the job done.

The transfer switch has the generator take priority when it is running. I use this feature all the time while dry camping. I have a small inverter generator that I connect to the shore power cord and use it to run the TV and top off my batteries. If I have a need for high power for a short period, say the microwave or whatever, I will fire up the big genny.

The transfer switch will then flip over to the generator feed for my power needs. When done I just turn off the big genny and it transfers back to my small one which is still running. Works like a champ. I would rather run the small generator to reduce run time on the big one which is a lot more expensive to service or repair. Also the small one uses a lot less gas.

I verified with the transfer switch manufacturer that switching over would not harm the switch. I never switch over with a heavy load, basically only the converter running.

[Antper]

Originally Posted by RetiredAndFree

When I exercise my generator, do I need to disconnect from my 30 amp shore power? I have been unplugging it before starting the generator off the battery.. I have a 2020 Greyhawk Prestige 30XP. Got it in July and run it once a month for about an hour. I know most say run it for 2 hours but I wonder if 2 hours is necessary.

I have Auto transfer and don't need to unplug BUT! I never run with multiple connections going on the same time. Devices do fail. Why chance anything.

[edatlanta]

Originally Posted by Antper

I have Auto transfer and don't need to unplug BUT! I never run with multiple connections going on the same time. Devices do fail. Why chance anything.

Agreed. I am on my 3rd auto transfer switch in 10 years of full time and I NEVER fire up the generator with shore power still turned on. I just switch off the breaker at the pedestal and then turn on the generator. And yes, I do check the tightness of the wiring lugs inside the transfer switch on a regular basis.

[Wireless Mike]

I have a Seneca and unplug B4 starting genny. Run for an hour but I DO put a load on it by hitting AC or heat pumps, make a cup of coffee, check the tv news; all basic functions you would normally expect it to support.

[Dgibbster]

As i have asked Jayco and they recommended to unplug shore when running generator. I would not trust the transfer switch even if equipped, not worth the possible troubles of overloading circuits.

[michael.g]

I never unplugged when on shore power to exercise the generator. We camped seasonally the last 2 years we owned the Greyhawk and exercised the generator each month.

Both the original Converter and the Inverter failed while we owned the Greyhawk, but the ATS did not.

-Michael

[msherw]

As has been said - ATS can fail to react due to a fault or age. I do kill the shore power for a big reason: Doing so lets me 'hear' the ATS cut on when the Onan is running. ATS will beep when it transfers.

Yes, always have some loading on your genset runs. A small 1500w box heater works or run the microwave. If summer, the AC is the ticket.

Good thread on the subject.

[JimD]

I contacted Progressive Dynamics, the manufacturer of my transfer switch, regarding firing up the generator while connected to shore power. I mentioned the only load at the time of switchover would be the converter. Their reply:

"You should have zero issues with what you are doing. The contacts should not get damaged at all."

I run my inverter generator on the shore power line at times while dry camping and leave it running when I briefly need the power of the big genny. I would NEVER switch over when a big load was present.

The transfer switch is really just a fancy relay. The only possible "damage" that could occur having it change states under load would be arcing of the contacts. The more load, the more arcing so it is best to keep it at a minimum.

A relay is designed to handle contact arcing. Just think about it, a relay is made to switch high loads. It has to be able to handle it or it would be useless. An example would be high power driving lights. You add a relay to switch the high amp load instead of using a switch to do the job because the switch contacts can't handle it.

So the moral of the story is to do what makes you comfortable. This sounds a lot like the drive with fridge on or off argument.