Community Forums

davidceder · 06-29-2021, 07:37 PM

I am in a park with very old infrastructure. I am only getting 105V out of the pedestal and every time I try to use an appliance my Progressive EMS cuts the power. I want to use the generator to cook dinner, etc. My thought was to kill the pedestal and use the Genny. Can I leave the power on and still fire up the genny. Does the genny have priority over the pedestal?

GrantR · 06-29-2021, 07:42 PM

If the power is that bad, I would unplug and use the generator. Leaving it plugged in can create issues for the transfer switch if you are pulling a lot of current and it decides to switch over. You can end up welding contacts. Exactly the reason you should turn off the air before plugging in if you are running the generator when you pull into a RV park.

96 Wideglide · 06-29-2021, 07:57 PM

I would follow Grant's recommendation.

I've been in your situation in an old RV park. Had to turn everything off, fridge on propane, so the wife could use her blow dryer.
When I enquired, the owner asked me if I had one of the fancy new surge protectors. When I replied "I certainly do", he advised I remove it, and all would be fine

.

Told him that ain't gona happen!

mahdi · 06-29-2021, 09:37 PM

In my coach the transfer switch has generator priority. If the genset is on, the house power is preferentially supplied by it and not the shore power from the pedestal. I would still recommend disconnecting the pedestal power if it is fluctuating that much and just get what power you need from the generator. That would be safer for the electronics and appliances on the coach.

I fully agree with trusting the surge protector.

twinboat · 06-30-2021, 03:54 AM

To answer the question, yes you can start the generator and the ATS will switch the power to generator. The generator has priority.

When you shut the generator off, it will switch back to shore power.

NCRog · 06-30-2021, 07:32 AM

Agree about the system having generator priority. However, I would be hesitant about just leaving it to do it on its own, the transfer could still take place with sufficient amperage to cause damage to the contacts … arcing and even potential welding of the contacts. I might be old school, but I always make sure the load is either off or as low as possible before making/breaking any circuit.

Rev. Roy · 06-30-2021, 12:04 PM

Quote:

Originally Posted by 96 Wideglide

I would follow Grant's recommendation.

I've been in your situation in an old RV park. Had to turn everything off, fridge on propane, so the wife could use her blow dryer.
When I enquired, the owner asked me if I had one of the fancy new surge protectors. When I replied "I certainly do", he advised I remove it, and all would be fine

.

Told him that ain't gona happen!

My answer would have been, "Seriously? Do I look stupid"? Trying to run most of these today's electronic devices when voltage is low can damage them. I have an Autoformer but have run into parks that have banned them.

twinboat · 06-30-2021, 01:43 PM

I find it incredible that the relay, that switchs the AC compressor on and off many thousands of times, is tiny in comparison to the ATS relay. Yet, we are cautioned to treat the much larger relay like fine China.

Sure the ATS contacts can wear over time, but its not like a thunder storm of sparks flying around in there.
Most failures are due to loose wire connections overheating and burning the connectors up.

tomgrigsby · 07-01-2021, 04:15 PM

Quote:

Originally Posted by twinboat

I find it incredible that the relay, that switchs the AC compressor on and off many thousands of times, is tiny in comparison to the ATS relay. Yet, we are cautioned to treat the much larger relay like fine China.

Sure the ATS contacts can wear over time, but its not like a thunder storm of sparks flying around in there.
Most failures are due to loose wire connections overheating and burning the connectors up.

That's a good comment and it got me to wondering what the transfer switch manufacturers say. The Todd ATS manual for my 2000 DSDP has a GENERATOR NOTE that states: "It is never advisable to start or stop a generator under load. To prolong the life of this transfer switch, and the life of the air conditioner, microwave, and other appliances, always turn those appliances off before starting or stopping the generator."

followingsea · 07-01-2021, 06:23 PM

I would never start the generator when plugged in or plug in when the generator is running. The ATS prevents bad thing from happening but I would not challenge it.

The ATS is a safety device for people who make make (all of us) and those who do know how things work.

Never challenge a safety device unless it under controlled test conditions.

In the navy I was qualified to supervise the operation of nuclear power plants. I was engineering duty officer when lighting knocked out shore power. Our emergency diesels started and there were various other things that had to be checked.

I heard an explosion and found my duty electrician had taken a fire ball to his face and his personal protective saved his life but he was injured.

Our equivalent of an ATS (bigger and more complicated) contacts has welded closed. We were no longer being protected from bad things happening.

In the case of an RV, bad things would just likely be a damaged generator.

Arch Hoagland · 07-01-2021, 06:27 PM

Turn everything off.

Unplug from shore power.

Start generator and wait until it starts producing power.

Turn on whatever appliances you want to run.

KenZ71 · 07-01-2021, 06:29 PM

Having to turn off the appliances seems to defeat the point of having a transfer switch.

Not doubting the benefits of turning things off just feels like using kid gloves

twinboat · 07-01-2021, 07:12 PM

I have been testing that and other theories for 8 years now.

I don't use a surge protector and I switch power by starting my generator and letting the ATS do its thing.

During our travel days, In the AM I cool the cabin with the dash AC. As the day gets warmer, I simply start the generator from the comfort of the drivers seat ( why else would the switch be there ) and that powers up the ready and waiting, rooftop AC.

You know what else switchs under load, the internal inverter/charger pass thru switchs along the external type powering resedental fridges.

followingsea · 07-02-2021, 11:16 AM

Quote:

Originally Posted by KenZ71

Having to turn off the appliances seems to defeat the point of having a transfer switch.

......

That is not the purpose of the ATS.

It is safety device. It prevents backfeeding the grid during a power outage and killing lineman.

It also prevents destroying your generator if it would connect to the grid out of phase.