Switching From Shore Power To Gen

[glsponchos]

When switching from Generator to Shore power and vice versa, do folks throw the main breaker first? 

I've heard some say to just turn off the AC and that is enough to prevent issues.  Thoughts?

[wolfe10]

This is one of those topics to which you will receive a lot of different answers.  They will range from "best practices" to "what I get away with".

I will start it off with what I consider are "best practices". This is how we do it when pulling into a CG and going from generator to shore power:

Assuming the generator is running under load (A/C's, likely converter or inverter/charger, perhaps water heater electric element, etc;), it is best for the generator to not go from heavy load to OFF.  Best to have a couple of minutes cool down period.  So, as Dianne goes into the CG office to check in, I turn off all loads (basically the roof A/C's, as I turn off the breaker for the electric water heater element when on the road).

As we pull into the camp site, the generator is turned off.

I check the outlet for voltage, polarity and ground, turn the CG breaker OFF and plug in. Then turn on the CG breaker.

We start turning on heavy loads, while monitoring voltage (voltage can be fine with no load, but drop very quickly if CG wiring is inadequately sized as you add load).

[wildebill308]

Brett's method is a  good practise. I  have found that my coach defaults to the generator if it is running so I have to shut off the generator first. I do like Brett and shut down all loads so I can let the generator run on light load for a while before shutting it off. 

I use a Surge Guard to plug into the pedestal to check the power. Always turn the power off when plugging in or unplugging from the pedestal. The Surge Guard will monitor the power and if it drops to low will automatically disconnect the power so it can't damage my coach.

Bill

[five]

Good advice.  If my coach is sitting in it's storage stall, plugged into shore power, I can turn on the generator (to exercise it) without unplugging from shore power.  When the generator is turned off, the coach automatically goes back to shore power.

[BillAdams]

I have a surge guard as well so once I plug into a campground it is going to take 2 minutes and 16 seconds before it switches to shore power.  Just before I am ready to plug in to shore power I shut down the A/C units.  After a short time I will shut down the generator which may or may not be before the shore power kicks in.  Since all the major loads are already off I will be able to shut down the generator safely.  Once the generator is shut down I turn things on as described by Brett above.

Going from shore power to generator is exactly the same.  I don't like to see the generator get hit with a huge load as soon as it becomes active so major loads like the A/C's are off until the generator has been running and providing 120V power for 20-30 seconds.  Then, just as with shore power, turn on 1 A/C, wait, turn on 2nd A/C.

[wildebill308]

I am with you Bill, I don't like to hit the generator with a big load till it has a chance to warm up a little. On my system the ems takes a while before it displays what is powered. I usually wait till the screen is lit up showing what has power and what the amp load is. Newer AC units should have a delay to let the head pressure dissipate so they start easier. My #1 unit starts first, the fan comes on and about 30 sec later the compressor kicks in then #2 does the same thing.

Bill 

[glsponchos]

Thanks folks

[RKSPAS]

Good Info...learned something helpful!