Generator Hookup help

[jmd]

Hello all, new to the site and I really like it.
Here's my question -How to hook up my old genertator to my fuse box.
Actually I would like to hook it up (backfeed) to a 100A subpanel in the garage, which in turn feed the main panel.
The generator is an old (Around 1992) Coleman Powemate 5000 / Model #PM54-5222, I have had it since new, starts right up.
My problem is pre 2000, the 30A plugs were 3 prong. Can I use the 3 prong 240 volt outlet on the generator and connect to a 30A receptacle and circuit breaker in the sub panel? There is a Groumd/ Bond/ Neutral Lug (not sure what the correct terminology is) on the generator that we used to hook up to a ground stake with a single pc of 10 wire, would I do the same or does this have to go back to the sub panel?
Thanks for any help.

 

[930dreamer]

I'd use the search function, many posts on this topic.


http://www.garagejournal.com/forum/showthread.php?t=112240&highlight=generator

 

[jmd]

dreamer, thanks for the response. I wasn't to worried about the back feed, I would do an Interlock switch, or a transfer switch. The same question is on the table, the 3 prong (non twist) receptacle on the generator. Thanks again.

 

[mrb]

first, you cannot feed into a subpanel and get electricity to your main panel (safely or legally). If you want power at the main panel, you need a transfer switch ahead of the main, interlocked backfeed breaker at main, or a similar arrangement. If you want the generator at the garage, you can put an inlet there and run it back to the main.

The 3 wire 240v receptacle is for 240v only. We had another poster ruin his electric boiler control the other day by connecting this to his house. Your generator will require modification to have a 4 wire receptacle with neutral. After this is done the N-G bond on the generator should be removed unless your transfer switch switches the neutral. (if using the generator for portable standalone use the NG bond needs to be put back)

 

[jmd]

mrb, thanks
Could you possibly elaborate on your second paragraph. There is a sticker (actually 2) that say if you back feed your house to make sure main breaker is off. That's why I thought the 240 would power up the panel, and not damage anything?

 

[mrb]

it doesnt matter what the 1992 sticker on the generator says, if you connect a generator to a builidng it has to be through a listed transfer switch. You cannot connect it and simply turn the main breaker off.

The 240v receptacle doesnt have a neutral. Generator to house needs 4 wires. Two hots, neutral and ground. The ground cant be connected to the neutral on the generator unless the transfer switch also switches the neutral. Connecting your house to 240v with no neutral causes the voltage to vary depending on load and will damage appliances.

 

[jmd]

So are you saying I need to by a newer 4 wire generator??

 

[jmd]

Could I put a new power head on it?

 

[mrb]

So are you saying I need to by a newer 4 wire generator??

no you just need to replace the receptacle with a 4 wire (L14-20 or L14-30 for 20 and 30 amp respectively) and wire it properly.

how do you plan to connect it? Again installing a transfer switch at a subpanel isnt going to get power back to the main panel.

 

[jmd]

Well, I am all ears now. The generator would not be used for anything else, other than backing up the house power when electric is down. I prefer to energize the panel and use an interlock switch. We have a well and the pump is a 1/2 hp, 220. I really like the idea of switching the circuits on or off depending on our needs thru the day. The receptacles are mounting into the power head. If I mount a new 4 wire receptacle would I just mount it somewher on the chasis. Could you tell me the 'Proper' wiring of the newli installed receptacle?

 

[mrb]

Well, I am all ears now. The generator would not be used for anything else, other than backing up the house power when electric is down. I prefer to energize the panel and use an interlock switch. We have a well and the pump is a 1/2 hp, 220. I really like the idea of switching the circuits on or off depending on our needs thru the day. The receptacles are mounting into the power head. If I mount a new 4 wire receptacle would I just mount it somewher on the chasis. Could you tell me the 'Proper' wiring of the newli installed receptacle?

can you post a picture of the power head with the receptacles? Also post a picture of your main panel.

 

[theoldwizard1]

Below is a drawing of transfer switch. This is an old picture and does not show a ground wire going back to the generator. If you look carefully there a 3 wires coming from the Main Power Line (2 hot and a neutral) and 3 wires coming from the generator (2 hots and a neutral). The switch (looks like an old fashion knife blade switch) connects either the Main Power Line or the Alternator (technically more accurate, but everyone calls them a generator) to the Main Fuse (Breaker) Panel. Note the neutrals are all connected in this drawing.

The ground inside your panel box comes from a cold water pipe or from a rod in the ground. It is "bonded" to the neutral in the panel box. You need a green insulated wire from from the ground bus bar in the panel box to the transfer switch box and then on the generator (via the cord). At the generator receptacle run another green insulated wire to the ground lug. You no longer need to connect this lug to anything else.

 

[theoldwizard1]

BTW, everything mrb is saying against "backfeeding" from the garage is accurate. There is no safe and legal way to do it.

It might work, but you are putting the linemen's lives in danger !

Note in my post the transfer switch is at the Main Panel !

 

[jmd]

mrb, sorry had to step out for a while. I'll get the pics and post them tonite or tomorow. Thanks again
If I can use the generator I have it would be great

 

[jmd]

While I am getting my pics together, I don't understand why you can't backfeed a subpanel. Are you saying you cant backfeed neither a main panel nor a sub panel or just not a sub panel? Seriously not arguing with you guys just trying to understand. Is the Interlock Kit device legal? I'll need to figure how to upload pics here also. Thanks again gang.

 

[mrb]

you can backfeed a subpanel (with a main breaker mechanically interlocked with the backfeed breaker with a listed mechanical interlock) or put a transfer switch inbetween the subpanel and its feeder.

what you cannot do is connect to a subpanel and send electricity back to the main

 

[jmd]

So here are some pics, I hope they can help you help me. Boy after I opened the receptacle cover I was a bit overwelmed.
Sorry some pics sideways

 

[jmd]

Here are the other pics

 

[mrb]

ok, i see that it can be modded to be proper but honestly if you are confused by the wires in there are you sure this is the task for you?

 

[jmd]

All the work you see in the main panel is mine, built new house did all wiring myself, inspector had no issues. This kinda thing is not covered in any books I have,, so if I can get some specific guidance I know I am capable of doing the work. Thanks

 

[theoldwizard1]

This is what mrb and I are having heartburn over

Actually I would like to hook it up (backfeed) to a 100A subpanel in the garage, which in turn feed the main panel.

Backfeeding is wrong, dangerous and should be illegal. Sure, technically it can be done in a "safe" manner. However, it requires a human to perform an uncommon task. If this step is done wrong/forgotten, a lineman can DIE

The only correct, safe and legal way to connect a generator is via a transfer switch at the feed to the MAIN PANEL.

Look at the picture I posted.

If you don't understand the 3 wire versus 4 wire issue, you shouldn't be messing with it !

 

[jmd]

Maybe I am missing something here. I am not saying I want to do anything that could hurt someone.
Lets put it this way - If I had a new generator (alternator) with a 4 wire twist plug, I don't think I would have any questions either using a transfer switch or a interlock switch. Where my confusion comes in is this older generator does not have a 4 wire anything outlet as you can see. So, how do I add a 4 wire receptacle safely and then what I would like to do because of flexibility is to use an interlock switch, the interlock prevents one from having the generator and the power grid feeding the board at the same time. If a transfer switch is the only way you guys feel comfortable giving me any advise then so be it, lets go down that road.

 

[mrb]

we still havent clarified you wanting to connect the generator to the subpanel in your garage....

 

[jmd]

we still havent clarified you wanting to connect the generator to the subpanel in your garage....

Just thought I could save material on the install. The sub panel is not critical that it be hot during a power outage. My main and meter is in the basement in the fron corner of the house, the sub panel is on the lower slope (basement front of house / ground level around back) at the attached garage about 70' away. The gen can not be located near the main panel, so that was the only reason I asked if it could go thru the sub. The more I thought about it, there is no sure fire way like the interlock switch that could be used to switch the Main and the gen breaker at the samr time if ran thru the sub, so I get that now.

 

[jmd]

If I had a sub panel ...I would ground gen case to sub panel ground..then gen H H N to H H N panel..meaning H to H is 220

But there is no surefire way of making sure when gen breaker is on, main breaker is off. I think I figured it out on my own why I shouldnt use the sub panel, people were just telling me not to but not why.

 

[mrb]

Just thought I could save material on the install. The sub panel is not critical that it be hot during a power outage. My main and meter is in the basement in the fron corner of the house, the sub panel is on the lower slope (basement front of house / ground level around back) at the attached garage about 70' away. The gen can not be located near the main panel, so that was the only reason I asked if it could go thru the sub. The more I thought about it, there is no sure fire way like the interlock switch that could be used to switch the Main and the gen breaker at the samr time if ran thru the sub, so I get that now.

Here is what you need to do to convert the generator:
you have two hot wires, one coming off each breaker that go to the 240v receptacle then jump to each half of the 120v receptacle. You would be taking both of these and the white neutral wire that goes to the 120v receptacle (the 2 neutral wires need to stay connected together). disconnect where the green ground connects to the white neutral. Get a L14-30 receptacle wire the 2 hots, neutral, and ground to it. Note the generator will no longer be suitable for standalone use -you will have to reconnect neutral to ground for that. Install a generator inlet (L14-30 seems to be most common) wired to the backfed breaker in your main panel -you will have to move some other breakers around as the backfed breaker has to be below the main. Purchase and install a listed interlock kit on the panel cover. Purchase a suitable length of 10/4 cord and install L14-30 plug and connector on it.

 

[mrb]

forgot: mount the L14-30 receptacle in a WP box on the generator frame, use a hole saw to make a hole in the appropriate location on the generator head cover and run a piece of sealtite from there to your box with the receptacle. Remove the receptacles on the generator head and make covers for the openings.

 

[mrb]

If you connect gen to sub panel ..you can back power your main panel ok..may sure your main breaker is off.. or meter out the socket...before starting gen...safety first is on you...

why are you telling someone to do something that is dangerous and illegal? Even if the OP doesnt take your advice someone else who doesnt fully understand could read your instruction.

 

[jmd]

mrb, thanks I'll give that a try.
I am curious, on the back of the cover what is the Blue capacitor thing for? What are the 2 yellow wires for? And what are the 2 brushes or mag in the plastic sheet on either side of the spindel bearing for?
If I have any questions, hope you dont mind if I write back.
I am going to start a new thread about running this gen inside, your input would be appreciated.

 

[mrb]

Yes its dangerous...but illegal??? Not for me..maybe for others...
If someone hires for work...that's different..
Jack up a car and get under it..that's dangerous too...

jacking up a car youre only going to hurt yourself. are there no codes where you live?

 

[mrb]

mrb, thanks I'll give that a try.
I am curious, on the back of the cover what is the Blue capacitor thing for? What are the 2 yellow wires for? And what are the 2 brushes or mag in the plastic sheet on either side of the spindel bearing for?
If I have any questions, hope you dont mind if I write back.
I am going to start a new thread about running this gen inside, your input would be appreciated.

running the gen inside, are you talking about running the wiring inside physically locating the generator inside?

the cap, other wires, and brushes are part of the excitation field I believe

 

[stevefasano]

removed due to

 

[purpony]

I just moved into a house that has a main switch shutoff outside the garage near my utility box. Just on the inside wall by that box is a 4 prong plug.
Would this outside transfer switch and the inside plug would be for the generator?

 

[mrb]

post pictures

 

[Lamtaipick]

Exactly same one I have.. Any one has a wiring diagram for this part.. Thanks

 

[nadogail]

My local utility showed a exhibition a few years ago an adapter that was inserted between the existing meter and the meter base to hook solar panels to your existing system.

Your POCO should be able to give you some guidance on this subject.

 

[slow]

My local utility showed a exhibition a few years ago an adapter that was inserted between the existing meter and the meter base to hook solar panels to your existing system.

Your POCO should be able to give you some guidance on this subject.

http://www.generlink.com/ is one brand similar to this, but many power companies will not allow them.