Need help adding a transfer switch

MrWizard wrote:
like wolfe said
its not about 240v
its all about having (2) 30amp 120v circuits from the generator to feed the RV that would normally have (2) 50amp circuits if using shore power, your gnerator is big for a 30amp transfer switch, you can't use all of the generator power, that switch is for (1) 30amp shore/generator feed
transfer switches have one output two inputs, the switch chooses which one is being used

you have a choice use only (1) generator circuit one hot & neutral
or get a 50 amp transfer switch, to switch both hots and the neutral

does the TT have a 30amp shore cord or a 50amp shore cord ?
or NO shore cord

The TT is a 50 amp transfer switch.

like wolfe said
its not about 240v
its all about having (2) 30amp 120v circuits from the generator to feed the RV that would normally have (2) 50amp circuits if using shore power, your gnerator is big for a 30amp transfer switch, you can't use all of the generator power, that switch is for (1) 30amp shore/generator feed
transfer switches have one output two inputs, the switch chooses which one is being used

you have a choice use only (1) generator circuit one hot & neutral
or get a 50 amp transfer switch, to switch both hots and the neutral

does the TT have a 30amp shore cord or a 50amp shore cord ?
or NO shore cord

"SUPPLIED JUMPERS" scream HIDDEN RE-CONNECT WIRE OPTION!

Meaning that is NOT SPECIFICALLY IMPLIED that it is for a reconnectable generator. It is IMPLIED that it cannot be used with a 6-wire reconnectable stator and that by following the manufacturer's instructions, a potential of seventy amperes capacity at 120vac would be available. To say this is confusing is an understatement.

It all depends on whether that model Onan has reconnectable stator leads.

Note the flagrant use of the embarrassing word IMPLIED. You need to get ahold of the DIPSWITCHES at ONAN and let them sort this out.

Side note:

My 1st 250Kw Onan job had me in stitches. The control circuitry had more current transformers than the 3rd Ave Ell. I had no choice but to purchase a thousand dollars worth of Onan service manuals. Onan made the 2.5Kw and the 6.5NH models simple to understand. The rest of the Onans seem to be blood brothers with the Rubik's Cube.

wolfe10 wrote:
If you have two hots, I would sure set up the breaker box with close to 50% of the loads on L1 and 50% on L2.

You do not mention what shore power you have-- if 50 amp, the above setup (split load between L1 and L2) is pretty much a given.

Thank you for the response! Shore power will only be 15 amp. Its a mobile dog grooming trailer. If not using the generator, she will be plugging into a standard 3 prong outlet at her customers homes using a long heavy duty extension cord.

The after the transfer switch setup is a little bit tricky because everything needs to go through our Xantrex Freedom 458 Inverter / Charger. She needs to be able to run all the equipment inside the trailer off the inverter batteries in the event the generator dies and she has no where to plug in to shore power. Any suggestions?? Can I not just use L1 and Neutral coming out of the transfer switch? If I do that, am I not using both power legs of the generator under load? This is where I'm a bit lost.....

88flaminchevy wrote:
Why is there a jumper installed between Neutral and AUX? Please someone correct me if I'm doing something incorrect.

Because as the directions say, you can use connect both L1 and L2 to the same 120V leg (giving up 240V) and if you do so, the neutral needs 2x the capability to handle both L1 and L2 in phase. They do this by doubling up aux and neutral. Seems a little hokey to me in that if aux or neutral were to fail in the transfer switch you'd end up overloading the other one without knowing it.

I'm not sure if your generator is dual 120V or 240V. If it's 240V, I'd leave it like you have it with L1 and L2 to the 240V "hot" legs from the generator and don't worry about the aux jumper or connection. You shouldn't have anything in the trailer connected to the aux terminal if you leave L1/L2 as 240V. Just because the generator makes 240V, it doesn't mean you need to use 240V. You can still use both "sides" at 120V each. In your trailer, connect your 120V devices across L1/neutral or L2/neutral in a somewhat balanced fashion.

If it's dual 120V (i.e. in phase), connect one white to neutral and the other to aux, but leave the shorting jumper in there.

If you only have a 120V shore power cord, you can feed both L1 and L2 of the transfer switch with the one hot feed. Be sure you have proper breakers that won't exceed the capability of the single neutral wire or shore cord.

If you have two hots, I would sure set up the breaker box with close to 50% of the loads on L1 and 50% on L2.

You do not mention what shore power you have-- if 50 amp, the above setup (split load between L1 and L2) is pretty much a given.