Firman Generation Installion

[JPaulChase]

I am a Proud new owner of a 2013 Big Country 2950RK. The first and (original owner) had the front compartment prewired and firewalled for an Onan generator by the factory. They could not afford the $4000++ Onan generator and neither can I. I have purchased a Firman 3200 dual / fuel generator with electric start from our Costco for a mere $799, with free delivery to my door, here at the end of the world in Ocean Shores, WA. It is capable of running the single AC with no other items running...it pasted that test, and is a lot quieter than the last Onan I had in a 2010 Class C RV.
1. Can I direct wire the generator into the electrical box they installed next to the generator compartment? I do not have any factory information. Based on wire color, it looks like it goes to the Model PD52 Automatic Transfer Relay Switch by Progressive Dynamics. There is second large wire bundle to the Tranfer Switch that probably comes from the rear of the 5th wheel where the 50 Amp plug connects. Right now I use a 20 foot cord and a 30 foot - 50 amp cord to get from one end of the trailer to the other. This electrical box is less than three feet from the generator.
2. Is it normal for a Automatic Transfer Relay Switch to receive power from two sources without flipping a switch? I would not be inputting power from two sources at a time.
3. Also Is it normal for an Automatic Transfer Relay Switch to make a loud bang sound when the 50 amp cord is plugged into it at rear of the trailer. When I first plugged in the 50 amp cord, I thought I blew up my 5th wheel. I even opened up the basement and removed the wall to see where the noise was coming from. I expected it to burst into flames. (a little fire caution/ paranoia left over from investigating fires for 24 years.)

Sorry for so many words. A couple of pictures would have helped you "see" my ?s ....but I am a new comer to the forum and do not have attachment rights. A picture is worth a 1000 words SORRY.

Paul Chase
Ol' Man at the Sea
Ocean Shores, WA
Getting ready to boondock in Quartzite, AZ where it does not rain 66 inches per year.
You input would be helpful.

 

[danemayer]

Hi Paul,

Welcome to the Heartland Owners Forum.

Taking your questions in reverse order:

3. The loud clunking noise is the contactors firing. It's like a large relay that activates either from shore power or from the generator power.

2. Receiving and managing 2 power sources is the purpose of the automatic transfer switch. The PD52 allows only 1 source at a time to connect to the wires going to the circuit breaker panel. It "prioritizes" generator power, which means if both power sources are hot, it activates the generator side and cuts power to the shore power side. The way it "knows" what's going on is that a circuit board requires 120V AC on the L1 wire in order to fire the contactors.

1. If you got the Firman W02981 Inverter Generator, your 30 Amp Firmin has a 30 amp 120V Travel Trailer receptacle that has a single hot wire, a neutral wire and a ground wire. The wires going to the transfer switch include 2 hot wires, 1 neutral, and 1 ground wire. To provide power to all of your circuit breakers, the single hot wire from the generator has to be Y'd to the 2 transfer switch hot wires.

Additionally, you may have to get or make a neutral/ground bonding plug for the 20 amp outlet on the generator. Some general purpose generators don't have neutral/ground bonding and you can run into problems using on an RV. You can read about neutral/ground bonding here.

Exhaust is something you'll have to figure out. The Onan generator has an exhaust pipe output. When installed in the front compartment, Heartland runs an exhaust pipe to the rear and out to the off-door-side of the RV. You'll have to examine the Firman to see how exhaust is handled. It may not be designed for an enclosed space like the front compartment.

 

[CDN]

Hello Paul.

I did this with my Landmark.

1. I added a 30 amp standard twist lock RV inlet on the front.






2. I moved the power feed from being buried in the back of the bay to the front. I Added a utility outlet I plug my Neutral/Ground bonding plug into and added a fuse holder with a 10 amp fuse. Gives me a spare outlet to check generator with a voltmeter. This the feed to the transfer switch.




My 4 kW Powerhouse Generator lives in the bed of my truck. Doesn't fit into the bay and it is not designed for this, too much heat and fuel tank enclosed is dangerous.

Brian

 

[LBR]

Our CY has the factory 5.5 builtin Onan. We rarely use it....most months it's only for an hour loaded down to exercise it.

Our main workhorse, a Firman 3300 gas, is always in the back of our truck with a 25' 30A cord plugged into shore power recepticle. The key fob start/stop was a selling point for me. Since I have the PI EMS in the trailer, I have to have the bonding plug. With close to 790 hours on it's clock, still purrs and is no louder today as it was day one. Hope your genset works out as sell for you also.

EDIT....we fulltime and if I had my 'ruthers', I would delete our 5.5 from that compartment and use said area for extra storage space.

 

[Gary521]

BY adding a Microaire to your AC's, you can run both AC's and then some with the generator that you bought.

 

[CDN]

BY adding a Microaire to your AC's, you can run both AC's and then some with the generator that you bought.

This is a god idea, waiting for warranty to expire then I plan on adding as well.

 

[JPaulChase]

Thank you all for your input. It is great to belong to a forum with experience and helpfulness to boot.

My Firman Inverter Generator is model WHO2942. It does not have the remote start...I am the "Honey please fire up the generator"model. It does have a 30 amp RV plug with a single hot wire, a ground, and a neutral. It also has a standard 110 duplex outlet. You are correct in saying that the prewired RV generator box contains a bare ground wire, white neutral wire , red hot wire and a black hot wire going to the Automatic Transfer. I understand that I need to Y the hot lead from my generator to the red and black in order to have all circuits working in my RV. (That appears to be the way a typical 4 prong 50 to a 3 prong 30 amp cord is designed.)

Heat and exhaust. I will have the generator exhaust aimed to the front of the RV. I will only operate it with the front compartment door open. I have a small fan blowing air into the compartment to cool and be sure fresh air gets to the engine air-intake at the rear. In another life I have investigated too many fires to not test it for fire safety.

I will need to do more research on the bonding plug. Thanks for the links. My Firman spec sheet says " AC Grounding System - Floating Neutral" I do not know if that is the same????

Regarding Microaire to your AC , from Gary , that will require more research. I see several videos on line from full timers that are adding that feature. Also FYI if you google just the word Microaire it goes straight to a liposuction procedures...not what most full timers in RVs are doing in their spare time. Sorry about that rabbit trail.

Thanks.

Ol' Man at the Sea
Paul Chase