Questions: 30a/50a Converter Plug, PI EMS, & Onan Generators

otrfun wrote:
Have plans to pickup our new toy hauler (with 50 amp capability) next week.

Couple Questions:

1. When you use a 30 amp to 50 amp pigtail converter plug, is the single 30 amp input simply placed in parallel with each/both of the TT's two 50 amp circuits?

Yes, the two "legs" on the 50 amp trailer/Motor home side are simply connected together.. So you can draw a total of 30 amps, but all curcuits inside are normally "live"

2. For those that use a 50 amp Progressive Industries EMS system with their on-board OEM 4000/5500 Onan generator, do you have any issues with the E4 ground error? I ask because I've found a bonding plug is necessary when using the 30 amp PI EMS with a portable Honda/Yamaha/Champion generator.

Thanks!

Not when using the adapter. The ground is still present and it still shows. Now the PI EMS (IF that is the one we usually call Surge Protector) Does not care if you are plugged into 30 or 50 amp, it works the same, if anything one of the functions works BETTER on 30, (but only one). That being spike supression.

The other kind of Energy Manager (load shedding) The kind that will turn off an A/C or the Water heater if you draw too much power.. IT does care if you are on 30 or 50.. It will stand down if it sees 240 volts (or close enough to it) across the legs, but if it sees the two legs connected together then it activates, Displays total amprage, and sheds as needed to keep you below 30.. one hopes.

This is very useful for those who have Mrs. Douglas Syndrom (TV SHOW Green Acers, Played by Eva Gabor) She was forever plugging in too many appliances and blowing the Generator.

CA Traveler wrote:
1. It protects the ATS
2. My gen will never have a failue! :B

1. An ATS is cheap, compared to all the electronics in the RV.
2. My gen had a failure. Stuff happens. (Glad I had the EMS immediately before the breaker panel.)

otrfun wrote:
Thanks for all the helpful replies. The 50 amp service on our new toy hauler is a bit new to me.

Trying to get ahead of everything before I pick it up Wed. I have plans to install a 50 amp EMS and a 2nd converter, a PD 9260, which I'll be paralleling with the OEM WFCO converter.

Hard to believe the OEM's continue to install these WFCO's :(

99% of RVers are clueless about WFCO chargers and they are cheap - As the salesman say you have this nice 50A battery charger...:S Make sure both chargers are compatible but regardless the WFCO probably won't contribute much charging.

There are many posts/opinions on where to install the PI unit. My HW50C is installed before the ATS for 2 reasons:
1. It protects the ATS
2. My gen will never have a failue! :B

But the big advantage for the HW50C for me is the inside remote. And yes I know some are satisfied with looking in the storage area or on the pedestal. :h

Thanks for all the helpful replies. The 50 amp service on our new toy hauler is a bit new to me.

Trying to get ahead of everything before I pick it up Wed. I have plans to install a 50 amp EMS and a 2nd converter, a PD 9260, which I'll be paralleling with the OEM WFCO converter.

Hard to believe the OEM's continue to install these WFCO's :(

The built-in ONAN generators GENERALLY come with a ground/neutral bond. Your EMS will PROBABLY not have a problem with it.

Here is a couple of simplified draws showing this...



30A-50A Dogbone Adapter (DMBRUSS)


Note the two HOT leads on the 50A side wired together on the adapter plug

Roy Ken

......

1. Yes, the one 30A hot is connected to both of the 50A socket hots. You naturally only have 30A available before the 30A breaker trips, spread between the two phases. (This does mean that any 240V circuits would not work, but essentially no RVs have 240V devices in them.)

2. Oftentimes people wire the EMS such that it comes between the shore power and the transfer switch, and so doesn't "see" the generator. However, it would not give this error when used with the generator because the built-in generator does bond neutral to ground at the generator. As the transfer switch is a three-pole switch, for the neutral and the two hots, this does not introduce a neutral/ground fault when connected to shore power.

If the built-in generator does not have neutral and ground bonded together, it's a faulty installation.