MEP-017a 240 plug

[mechanix]

I want to install a 240v plug on my gen so I can use a generator cord for hookup. I know the two hot leads will go to L2 and L3. Do I need to run the neutral to the S1-2 terminal? That way I don't need a jumper so if need be I can use the other settings with out removing it.

 

[Beerslayer]

I have the same genset. The way I read the manual, there is no 120/240, just 120 ~OR 240. I hope I am wrong.

For 240VAC you don't need a neutral, just two hots. What is the NEMA number on the plug you are hoping to use? That would tell me what the specs are on it. For example is it a NEMA L14-20R? Here's some links to the NEMA specs to help you out, but it should be on the plug as well.

NEMA Configurations

NEMA connector - Wikipedia, the free encyclopedia

 

[mechanix]

I was going to use the L14-30 plug. I need a neutral hookup as I am planning to hook it up to a sup pannel when power goes out.

 

[Carl_in_NH]

What you need is 240V/3 wire, which the MEP-017A does not do in its stock configuration; it only does 120V/2 wire, and 240V/2 wire without modification. There are threads floating around the board that point out the modification you need to make in order to bring out a neutral connection. The other thing you can do is run it in 3 phase mode, and use 2 phased and neutral for a 208V 3 wire output, but the genset output power will be reduced by 33%.

 

[mechanix]

I found some stuff on smokstak and I saw on there to hook up to the S1-2 terminal for neutral so it looks like that is what I am going to do. I am going to do that and switch it over to propane.

 

[Beerslayer]

I found some stuff on smokstak and I saw on there to hook up to the S1-2 terminal for neutral so it looks like that is what I am going to do. I am going to do that and switch it over to propane.

Would you please link to what you found on Smokstak?

I need to pull out a neutral as well.

If you hook up to your house power you will need to put in a transfer switch as well. The manual switches are not expensive.

Thanks!

 

[84blue69]

That is correct the s1-2 term. I hooked a 12in piece of 8awg tthn and shoved it through the louvers and just wire nut it. i plan on installing a plug. However i never think about it till a power outage.

 

[mechanix]

I am going to hook it up to the house side of a 60A breaker that feeds the panel for the addition on the house. I am going to put a disconnect between that and the gen plug so it isn't hot so no one can open the cover and stick there fingers in it and get shocked. Well at the least anyway. This is a little of what I found on smokstak.
3 Phase Dsitribution - SmokStak

 

[Beerslayer]

I am going to hook it up to the house side of a 60A breaker that feeds the panel for the addition on the house. I am going to put a disconnect between that and the gen plug so it isn't hot so no one can open the cover and stick there fingers in it and get shocked. Well at the least anyway. This is a little of what I found on smokstak.
3 Phase Dsitribution - SmokStak

Thanks for the SmokStak Link, I appreciate it.

So your idea of using a disconnect to keep the plug safe is good as far as it goes.

What it does not address is the fact that if you back feed your panel through a breaker you will be energizing the utility lines by back feeding into the grid. It is very dangerous for the utility workers who are trying to get your power turned back on.

How about installing one of these at the very least?

 

[mechanix]

I wont be backfeeding as I will be turning the breaker off. I will be feeding power in on the load side of the breaker not the line side.

 

[Isaac-1]

There are many horror stories online about people back feeding like you describe. The example I like to use was posted on the Smokstak board a couple of years ago. It was posted by a guy that "knew what he was doing" during a multi day outage, he had the main breaker turned off, and was back feeding the whole house through another breaker on the panel. He even taped the main breaker in the off position with a note saying not to turn on, on the third day of the outage he was called away from the house for a couple of hours, while he was gone the power came back on, and his teen age son took the tape off the main breaker and flipped it back on....

 

[mechanix]

I am not backfeeding. I will be hooking up to the lines that feed into the supanel. I will be turning off the 60A breaker that feeds the subpanel.

 

[Isaac-1]

The point is backfeeding could occur like it did in my example if someone turns on the breaker without first disconnecting the generator, unless you install a propper transfer switch, or at least a breaker safety interlock device like shown in the above link. This could potentially kill a lineman if the power is still out, or destroy your generator and injure or kill the person flipping the breaker if the power was back on. Even if we assume you know not to do this, is this true for anyone that might have access to the panel?

Ike

 

[mechanix]

I can lock the cover on the 60A disconnect so no one can mess wwith it.

 

[Carl_in_NH]

I'm on Ike's side here; it doesn't cost much to insure safety. Make shift work-arounds have their place - like during an ice storm when you've got no other way to restore power to your house. If you're doing an install to make things plug-and-play in the future then it's worth doing right.

It sounds like you've convinced yourself that what you're planning on doing is just fine. I, personally, disagree (as does code).

 

[Beerslayer]

I am not backfeeding. I will be hooking up to the lines that feed into the supanel. I will be turning off the 60A breaker that feeds the subpanel.

It is certainly not your intent to backfeed, that is clear enough, but as others have pointed out, it could happen. I like your setup with a sub panel, and it would be very easy and inexpensive to put in a manual transfer switch to isolate just your subpanel. Without it is illegal.

Under a certain amperage, transfer switches are inexpensive. The electrical code ensures safety, it really is a benefit to all.

I have been wondering how to do this myself without going through the hassle of putting in a new service, now I know:

1. Install a 50 or so amp sub panel fed from the main panel through a manual transfer switch.

2. Separate out the loads that I want on the generator, splice them in the old panel and bring them into the subpanel.

Easy. Safe. Economical. Going to do it.

In our neighborhood, during an outage if the power company crews hear a generator running that is not on their records as being connected through a transfer switch, they will just leave the power off and go somewhere else. Don't think that would make me many friends with the neighbors.

Did we get off topic?