30 amp to 50 amp

[Bob Denman]

That's why I figured it best to stay out of this fight...
Although I DO have one of those plugs that is supposed to allow me to hook my 30 amp cable up to the "Big-Rig" 50 amp receptacle...

I just don't want to end up like this kid!

https://www.youtube.com/watch?v=vSMjhlBtq_g

[Porkchop]

OK gritz, it will work in a non GFI situation. But most on here are wondering about RV parks, so my answer stands. It will not work in most campgrounds, as I originally stated.
I don't care about your brothers garbage mans cousins neighbor or how many generators he has. AND you need to research about return current on a neutral wire and how to overload and damage it.
And I am an electrical engineer. Thankfully retired now.

Jamie, I have, and know lots of others who have 240v dryers in their rigs. I know 2 people who have 240v electric ranges in their rigs.


Farm on!
Bill

[The Gritz Carlton]

Thanks for confirming I am right.

[JamieGeek]

Originally Posted by Porkchop

OK gritz, it will work in a non GFI situation. But most on here are wondering about RV parks, so my answer stands. It will not work in most campgrounds, as I originally stated.
I don't care about your brothers garbage mans cousins neighbor or how many generators he has. AND you need to research about return current on a neutral wire and how to overload and damage it.
And I am an electrical engineer. Thankfully retired now.

Jamie, I have, and know lots of others who have 240v dryers in their rigs. I know 2 people who have 240v electric ranges in their rigs.


Farm on!
Bill

Which is why I qualified that with "as far as I know". Interesting that they have built RV's with 240V appliances.

[Chance]

Originally Posted by JamieGeek

Which is why I qualified that with "as far as I know". Interesting that they have built RV's with 240V appliances.

Jamie, I think L1 and L2 have always been at 240 Volts on 50-Amp service, otherwise the neutral conductor could see up to 100 Amps. I suppose some campgrounds could be miswired so voltage between L1 and L2 is zero, but I expect it’s extremely rare.

[Cummins12V98]

"As far as I know: No appliance in any 50 amp RV actually requires 240 volts to operate--instead they just use the two 120V legs as two separate 50 amp circuits.

Grasshopper, I have news for you. My Clothes Washer and Dryer BOTH are 240V appliances.

My Cummins Commercial 6500 gen is 240V and it will run them as a standard gen is only single phase.

[JamieGeek]

Originally Posted by Cummins12V98

"As far as I know: No appliance in any 50 amp RV actually requires 240 volts to operate--instead they just use the two 120V legs as two separate 50 amp circuits.

Grasshopper, I have news for you. My Clothes Washer and Dryer BOTH are 240V appliances.

My Cummins Commercial 6500 gen is 240V and it will run them as a standard gen is only single phase.

LOL, read carefully: "as far as I know" a bit of a qualifier stating that I don't know everything. Which Porkchop above also confirmed.

[Cummins12V98]

Originally Posted by JamieGeek

LOL, read carefully: "as far as I know" a bit of a qualifier stating that I don't know everything. Which Porkchop above also confirmed.

HA, yes I understand as I was trying to expand your RV knowledge!

[clev]

I posted this on another thread,. It doesn’t matter how many amps you can provide to your 50 amp plug. If it’s 110, the electronics will limit the power to 30 amps; period. I’’ve done this with two 3500 watt inverter generators, connected with a parallel kit. With 7000 watts, I have almost 60 amps available, but the electronics limit it to 30. In order to get full amperage, you must ‘trick’ the system into thinking that you’re running an onboard generator. Then, and only then, can you get more than 30 amps.

I should clarify; my coach is a 36RSSB3 with 2800 Magnum, Surge Guard, wired for generator, etc. if your coach is older, or does not have these electronics, you may not have limitations.

[16ACE27]

Originally Posted by clev

I posted this on another thread,. It doesn’t matter how many amps you can provide to your 50 amp plug. If it’s 110, the electronics will limit the power to 30 amps; period. I’’ve done this with two 3500 watt inverter generators, connected with a parallel kit. With 7000 watts, I have almost 60 amps available, but the electronics limit it to 30. In order to get full amperage, you must ‘trick’ the system into thinking that you’re running an onboard generator. Then, and only then, can you get more than 30 amps.

I should clarify; my coach is a 36RSSB3 with 2800 Magnum, Surge Guard, wired for generator, etc. if your coach is older, or does not have these electronics, you may not have limitations.

No. You have a major misunderstanding of electricity.

Voltage is supplied (as in 120 VAC, 12 VDC, 240 VAC)
Current is drawn by the loads attached to the supplied voltage.

The "30 Amp" and "50 Amp" designations are maximum designed current for the connection.
That's why there are breakers that will trip when excessive current is drawn.

The current is not limited by any magic electronics and there is no system to "trick".

[clev]

I don’t come on here to argue and have never professed to be an expert. I have a basic knowledge/understanding of electricity which has served ‘me’ well.

I posted fact on the 30 amp limit. This was based on using 2 separate pairs of generators on more than one occasion, and using a Camco ‘Y’ connecter with 30 amp plugs on each arm and a 50 amp female on the leg. No matter what I did, my coach was limited to 30 amps, and 30 amps would be lit on the display.

After calling tech support, more than once, a tech finally explained to me why the coach only had 30 amps when more was available. After doing the one wire mode to the onboard generator wiring as he described, I now have full amperage, regardless of whether I’m using two generators or two 30 amp plugs in an rv park. I just used this setup with the ‘Y’ adapter in an Okie City Park that only offered 30 amps at my site. So, apparently, Mr Fryman, you have less of an understanding than I do.

[16ACE27]

Originally Posted by clev

I posted fact on the 30 amp limit. This was based on using 2 separate pairs of generators on more than one occasion, and using a Camco ‘Y’ connecter with 30 amp plugs on each arm and a 50 amp female on the leg. No matter what I did, my coach was limited to 30 amps, and 30 amps would be lit on the display.

Well, my explanation applies to electricity in general, not to some unknown application of generators in parallel attached to some unknown Camco adapter and some unknown modification of the generators (as opposed to the coach). Was your "30 Amps" displayed on the generators? or maybe an EMS in your RV? An EMS is the only magic electronics that will limit current to your RV. And if you have a 50 Amp coach and you don't supply L1 and L2 180 degrees out of phase the EMS will only see it as a 120 VAC input (instead of 240 VAC across L1 and L2) which in the RV world is a 30 Amp standard.

[Porkchop]

Tfryman=Don't waste your time trying to explain something to someone who is delusional in that he knows more than everyone else. It wastes your time and irritates him. Been there, done that. Some people are not willing to learn.

Bill

[JamieGeek]

Giving clev the benefit of doubt: I believe he is describing the system on his DRV which may very well be completely different from all the Thor motorhomes.

That system was discussed in some of the other DRV threads where everything is limited to 30amps by the converter/controller/etc. unless a specific "trigger" wire had 240V on it or something like that.

So all I'm seeing here is just miscommunication/misunderstanding.

We're all good...

[16ACE27]

No such thing as "50 amp, 120 volt service". Your situation is not DRV specific. As I mentioned earlier, if a 50 amp coach has an EMS installed (Electrical Management System) and it does not see the correct 240 VAC coming into the coach between L1 and L2, it will limit your current to 30 amps unless you tell it you are on a 20 amp or 15 amp service circuit. This is an EMS function and your anecdotal experience does not apply to a coach without an EMS installed.

[Porthole]

Originally Posted by Tfryman

No such thing as "50 amp, 120 volt service". Your situation is not DRV specific. As I mentioned earlier, if a 50 amp coach has an EMS installed (Electrical Management System) and it does not see the correct 240 VAC coming into the coach between L1 and L2, it will limit your current to 30 amps unless you tell it you are on a 20 amp or 15 amp service circuit. This is an EMS function and your anecdotal experience does not apply to a coach without an EMS installed.

How does that apply with DRV's use of the mini PCS installed when on generator?

If not on 50 or 30 amp shore power, obviously the system is not going to do anything. But, if the generator hour meter is running, the PCS uses the signal to bypass the limitation and allows the generator to supply it's full power to both sides of the panel, even if it is only a 5500 watt generator. The point being the 30 amp (or 20-15) limit is not used.

I think that is what Clev is trying to do with his portable generators.

Unless my instruction page is wrong.

[fhenn]

Okay time to stop this discord I will close this thread.