Generator Power Transfer Switch

[Community Alumni]

I am considering the installation of an automatic power transfer switch with a time delay on our Navion 24G. This arrangement would bypass the 30 Amp outlet and power cord. This arrangement would eliminate the resistance of the power cord, provide an auxillary 30 Amp outlet for external use and a time delay to protect electrical appliances by allowing the generator voltage to stabilize. Any flaws to this logic?

[ronfisherman]

FunTwoDrv wrote:
Great info...thanks! I think I have the transfer switch figured out. I now need to do some research on modding the geni to automatically start. I like the systems on the newer RV's that start the geni if inside temps exceed a preset temp.

Gary

Checkout a Magnum Energy. ME-AGS-S. It will work on most generators.

[FunTwoDrv]

Great info...thanks! I think I have the transfer switch figured out. I now need to do some research on modding the geni to automatically start. I like the systems on the newer RV's that start the geni if inside temps exceed a preset temp.

Gary

[beachcomber_1]

Did this last month, best mod that I have done to my C.

[77rollalong]

what i did on one travel trailer was put a female plug on the gen, then plug the trailer into the gen, a friends class C has a built in gen, where the power from the gen, goes to a female plug in the power cord storage, so when you don't have shore power, you plug the motorhome into the socket in the storage box. Ours does have an auto power transfer switch in the fuse box inside with a 30 sec delay on start up..

[bukhrn]

I never realized there were so many that came without the Transfer Switch not built in. :h

[BruceMc]

Additionally, I installed a Marineco 30A 120V connector in place of the rabbit hole for the shore cord:



If I didn't have the transfer switch, the terminals under the cover would be live/hot while the generator was running.... not a good thing.

The shore cord was threaded into, and stored in a large rear compartment. Thus, I had a lot of room to work on this project.
I used the 4x4x2 electrical box originally housing the 30A socket as a backer to this connector, otherwise, the wiring would have been a pain.
Within the storage compartment, Had I desired to do so, I could have added that box & 30A connector to the outputs of the transfer switch, but didn't see any value in having it there. A 120V 15A would be more useful.

The end result was:
o No shore cord haphazardly stored in the compartment, now it is coiled up & in a nice storage box along with the other 12Gauge extension cords & adapters
o No bulky shore cord to drag out of the rabbit hole & connect, now if I want a lighter connection (15A) where I don't have a heavy load (uW, converter/charger, etc.), I can plug in a short adapter and a 15A cord. Much easier....
o No hole in the sidewall for critters to use as an entry point when the shore cord is deployed.

[BruceMc]

This is the unit I put in our new Sunseeker: PD5110010 120 VAC 30-Amp Automatic Transfer Switch.
There's two inputs and one output - one input used the terminals in NC (Normally Closed) position, the second input energizes the relay, thus those are NO (Normally Open). A circuit module built into the unit delays the output transfer for 20 - 45 seconds.

Download the owners/install manual: Installation and Operation Guide for PD5100 Automatic Transfer Switch

I put the generator on the NO input so it would energize only when the generator was running. The shore cord connects to the NC inputs, thus the relay is not energized. The generator will be used for about 0.5% of the time vs connected to shore power.

The terminals are labeled for the various inputs. You shouldn't have any difficulty installing it if you are comfortable with basic wiring.

[FunTwoDrv]

I like this idea...is there a DIY or other info someone could point me to to learn more about how to install one in our C? It looks like we would need the switch along with some way to start the generator. Ours uses a "prime" button so, auto starting it might mean additional mods to the generator.

Gary

[DrewE]

That's exactly how many many motorhomes are wired up (namely, those that come with an automatic transfer switch rather than use the socket setup with the generator as you have). The logic is sound and the setup perfectly reasonable. The one difference is that most don't have the extra 30A receptacle wired anywhere.

Are you planning on having this receptacle wired just to the generator, in parallel with the transfer switch, or to the output of the transfer switch, or to a circuit from the electrical panel? I think any of the options would be workable and legal and safe, but I myself would probably prefer it be powered from the electrical panel so as to have at least the 30A RV main breaker protecting it.

[1995brave]

No problems. Remember to put the time delay on the generator side. That 30 seconds allows the generator to stabilize. Did the same to my 95 Brave when I had it.