Turning on the genny while connected to limited shore power?

[Ron_H]

In our two years of full timing I have never before run into a situation where we've connected to a standard 15 amp household electrical connection.

We're currently parked in the driveway of some distant family and we're going to connect our coach to their house using a standard electrical outlet. I know it will provide limited amperage but enough to keep may coach batteries charged up. What I do not know is how the system will handle turning on the generator if we want more power, such as to run our air conditioners.

Do I have to disconnect the shore power before starting the genny or does it automatically draw from the greater power source? I don't want to chance damaging anything or tripping one of their breakers.

[Pa Miller]

You need to be very carefull switching from shore to gen or visa versa .... make sure ac or nothing major is on....... it will blow the voltage regulator on your gen..... don't ask how I know.. let the gen run and warm up before and after using ...

[twinboat]

After a 30 second or so delay, for the generator to stabilize, the power will disconnect from shore power and connect to the generator power. There is nothing you need to do.

I would only caution you that if the generator stops while running the AC, the shore power may trip it's circuit breaker.

If you can find a 20 amp circuit ( kitchen, dinning room, laundry room outlet ) you may be able to run your AC on your shore power.

I have, a number of times.

[hawgguy]

Originally Posted by Ron_H

Do I have to disconnect the shore power before starting the genny or does it automatically draw from the greater power source? I don't want to chance damaging anything or tripping one of their breakers.

Every automatic transfer switch I have had in an RV will preferentially draw from generator power over shore power - regardless if it is 10 amp, 30 amp or 50 amp.

I have remained plugged in with the generator running. The only crucial time, as previously mentioned, is when you decide to stop your generator - make sure your heavy draws (air conditioner, wife's blow dryer) are off. I do that as part of my routine anyway in switching from generator to pedestal and visa versa to minimize the stress on the ATS.

[mel s]

Originally Posted by Ron_H

In our two years of full timing I have never before run into a situation where we've connected to a standard 15 amp household electrical connection.

We're currently parked in the driveway of some distant family and we're going to connect our coach to their house using a standard electrical outlet. I know it will provide limited amperage but enough to keep may coach batteries charged up. What I do not know is how the system will handle turning on the generator if we want more power, such as to run our air conditioners.

Do I have to disconnect the shore power before starting the genny or does it automatically draw from the greater power source?
I don't want to chance damaging anything or tripping one of their breakers.

Ron_H
When my genset is started, (running), my ATS, (automatic transfer switch), automatically defaults to, (chooses), generator power.... whether there is 15A, 20A, 30A or 50A shore power OR no shore power at all.
(No need to disconnect the shore power before starting the genny).
Mel
'96 Safari

[Mich F]

You can turn on your generator, while hooked up to that 15A line, but to be on the safe side (things can/do go wrong), I would disconnect that shore power line before starting the generator.

[MisterT]

no need to disconnect, the ATS built into your coach, if so, provides the necessary transfer of power from the Generator - when it stops, the ATS will revert back to any other incoming power source, ala your 20a service.
Could it trip your breaker when it reverts to 20a? sure, as a possibility, but as a Probability, probably not, unless you have added more amperage items than it can handle.
I usually also turn my SHORE setting on my Magnum charger to 5 or 10amps when only connected to 20a since it then limits tripping of the breaker due to the charger trying to pull too many amps for charging.

[bud01234]

Originally Posted by Mich F

You can turn on your generator, while hooked up to that 15A line, but to be on the safe side (things can/do go wrong), I would disconnect that shore power line before starting the generator.

I have no choice- I have to move the 30amp cord from the pedestal to the genny. I always turn off everything, turn off circuit breakers on the pedestal, unplug from pedestal and plug into genny then start genny. After a few minutes, start turning on a/c, etc. Not very automatic but works well.

[Mich F]

Originally Posted by bud01234

I have no choice- I have to move the 30amp cord from the pedestal to the genny. I always turn off everything, turn off circuit breakers on the pedestal, unplug from pedestal and plug into genny then start genny. After a few minutes, start turning on a/c, etc. Not very automatic but works well.

I didn't have a choice either on my current MH, until I added an ATS. I also added a Progressive Ind. EMS. I also don't trust things like an ATS to always function as they're supposed to, which is why I suggested the OP disconnect power before starting his generator. A minute or so of "work" could possibly prevent the unexpected from happening.

[Spk64]

Yes, ATS will switch automatically and most of the time Generator has priority over everything else. But to save wear and tear on the ATS contacts, it is best to turn off any heavy loads before allowing it to switch automatically. Most AC systems have timers so once the ATS does make the change then the loads can be switched back on and the AC will wait a safe amount of time before kicking on.


Steve

[vsheetz]

Yup, ok to switch over to genny or back to shore with shore connected as long as no large current draw items are active. Else you run the chance of damaging the automatic transfer switch. And the damage to the transfer switch is likely not immediate, rather cumulative over time.

[Pa Miller]

Before starting the generator , Make sure all 120 volt appliances are turned off.. After starting the generator allow its engine speed to stabilize before turning on appliances also turn off all 120 volt appliances before shutting off generator .... copied from Monaco owners manual ..

[twinboat]

Originally Posted by twinboat

After a 30 second or so delay, for the generator to stabilize, the power will disconnect from shore power and connect to the generator power. There is nothing you need to do.

I would only caution you that if the generator stops while running the AC, the shore power may trip it's circuit breaker.

If you can find a 20 amp circuit ( kitchen, dinning room, laundry room outlet ) you may be able to run your AC on your shore power.

I have, a number of times.

A word of caution on laundry room outlets. Only use the standard washing machine outlet.

If you want to use a electric dryer outlet, you need to know what your doing with 240 volt power. If you don't, don't try.

[mel s]

Originally Posted by Mich F

I didn't have a choice either on my current MH, until I added an ATS. I also added a Progressive Ind. EMS. I also don't trust things like an ATS to always function as they're supposed to, which is why I suggested the OP disconnect power before starting his generator. A minute or so of "work" could possibly prevent the unexpected from happening.

Mich F
Why did you bother to add an ATS if you "don't trust things like an ATS to always function as they're supposed to".
Wondering
Mel
'96 Safari