Using MH Gen Set to Power House

[BIGRED1]

I have a 7.5KW Onan diesel gen set in my Monaco Diplomat. I was wondering about the possibility of putting a receptacle on it so that it could be connected to my house for back up purposes during a power outage. Is this feasbile and has anyone done this that could share what was needed to do it?

TIA!

[BIGRED1]

I have a 7.5KW Onan diesel gen set in my Monaco Diplomat. I was wondering about the possibility of putting a receptacle on it so that it could be connected to my house for back up purposes during a power outage. Is this feasbile and has anyone done this that could share what was needed to do it?

TIA!

[Tom N]

You can do this but code requires that you use a transfer switch so it is impossible for the coach generator and the grid power to be hooked to the house at the same time. If you feed power back into the grid you could kill a lineman.

[rhkh]

I do this sucessfully as follows.
First, I installed a trasfer switch in the motorhome panel that allows the output of the generator to be connected to the shore power cable.
Second, one must disconnect the house from the power grid. I do this by opening the main power disconnect breaker on my house power panel.
Next, start the motorhome generator, flip the transfer switch on the motorhome panel and it will power one leg of the house circuits.
I have to be carefull that I do not put too much load on the generator, else I will pop the generator output breaker.
When our house power goes out I merely power the house from the generator easily. However, none of the house 220 volt loads will operate.

[Tom N]

rhkh;

What you are doing is illegal. You need a transfer switch so it is impossible for you to feed power to the grid if you or someone else closes the main breaker on you panel.

Call your local electric provider for further information if you want to be legal.

[NeilV]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Tom N:
rhkh;

What you are doing is illegal. You need a transfer switch so it is impossible for you to feed power to the grid if you or someone else closes the main breaker on you panel.

Call your local electric provider for further information if you want to be legal. </div></BLOCKQUOTE>


Tom's right you need to make this right before someone gets hurt.

Even with a transfer switch you are still out of code. You never should provide power out the male end of a cord. I had a 50 amp outlet on my last coach which could be used to power a second coach when dry camping or to safely feed a transfer switch on a houses power panel. The outlet was off the 50 amp mains of the coaches power panel and protected by the main breaker in the coach.

[Ray,IN]

Tom, Neil, it depends upon what state regulations say. Indiana just says to disconnect from line power before using a genset.
To reinforce your advice though I'll add this: About 25 years ago a diary farmer in North Indiana used his brand new back-up genset to provide electricity for his milk cooling units during a ice storm. He forgot to throw the disconnect switch. When the linemen approached the downed lines up the road, they detected power in them. They used the approved shorting device to deaden the lines, in the process destroying the farmers genset. When the farmer complained to the REMC and demanded a new genset they called the sheriff. The farmer wound up losing his entire dairy business.

[NeilV]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Ray,IN:
Tom, Neil, it depends upon what state regulations say. Indiana just says to disconnect from line power before using a genset.
To reinforce your advice though I'll add this: About 25 years ago a diary farmer in North Indiana used his brand new back-up genset to provide electricity for his milk cooling units during a ice storm. He forgot to throw the disconnect switch. When the linemen approached the downed lines up the road, they detected power in them. They used the approved shorting device to deaden the lines, in the process destroying the farmers genset. When the farmer complained to the REMC and demanded a new genset they called the sheriff. The farmer wound up losing his entire dairy business. </div></BLOCKQUOTE>

Ray,

The National Electrical Code is the standard that is usually followed when there is a loss of life or property. The non-complient are found negligent for "failing to adhere to well known best practices for safety". The NEC or NFPA 70 are recognized as the most well know best practices and will be what the courts would most likely follow. Even if the negligent practice was allowed by the local buiding inspector and is allowed in the local buiding code this does not provide absolution.

According to the Encyclopedia writeup on the NEC:

"In the U.S., anyone, including the city issuing building permits, may face a civil liability lawsuit (be sued) for negligently creating a situation that results in loss of life or property."

So while the Indiana State Regs generically says to disconnect from line power before using a genset the "well known best practices for safety" outline how to disconnect from line power.

Putting power out of a male plug end is another matter.

Be safe and follow best practices no matter what poor practices local regs may let you get away with. We only end up cheating ourselves when we cheat on safety.

Kindest regards,

[BIGRED1]

So, I should have a transfer switch installed in the house, right? I assume one that would give the utility power priority, but if it wasn't present and the gen set power was it would allow it in? Would this be installed before the utility company's meter? Where would I need to tap into on the gen set to get the power over to the transfer switch?

TIA!

[rick_od]

The right kind of x-fer switch does the following. It has two switches / breakers on it. One for commercial power and one for genset power. It is designed so that it is impossible to have both on at the same time. ie. when commercial power is on, genset power is off & when genset power is on, commercial power is off. The x-fer switch is placed between the meter and the electrical panel.