Help wiring my indian 4kva gen head

[greasy_burger]

Hi everyone,

I just got my metro lister 6/1 and 4kva gen head and would like to wire it for a few 120v receptacles in a temporary box, I have a small subpanel I may use also, the genhead has 3 terminals 2   120v terminals and one marked n( nuetral?) what is the easiest way to safely get say 4 receptacles wired for temp use? and does this need to be grounded and if so what is the easiest method? please bear with my basic questions but it's a learning curve for me:)

[biobill]

Greasy Burger,
  You have 120v available between either "P" terminal and neutral, but only at half rated power. Between the two "P" terminals you have 240 at full rated power. I'd suggest sending 240 to your subpanel and taking the 120 from there. The panel should be grounded but I'll leave the rest of the grounding issues to someone wiser than I     Bill

[greasy_burger]

Thanks Biobill, that's pretty much the conclusion I came to, I have a small subpanel that I am going to use, it should work well:)

[Doug]

The panel should be grounded.

Grounding and bonding are best understood if you buy a copy of the electrical code simplified for residential wiring.

Should is a rather weak word. Absoluetly must are much better ones......

[xyzer]

Wiring is not my expertise for sure.....but correct me if I'm wrong..... if the generator is not grounded with a ground rod it still aint grounded!?
Dave

The panel should be grounded.

To a ground rod....correct?

[Doug]

Depends on aplication and location.

You may be able to use your home ground and simply bond everything to the house grounding system.

You may have your own completely isolated system with rod and lighting panel for the generator only.

You ground once with a rod or plate and that connection is brought up to the common bus once and in one place only. Everything else is simply a bond ( bare copper wire that connects all metal parts to the gound bus in the main panle ). Bonds only tye things together and pull them down to ground potential in other words. Ground is the big single point that provides that return path and refernce.

Like all things there are some exceptions and in some cases you are allowed to do things differently but you must understand grounding and bonding if you are going to do any serious new wiring. 

[biobill]

greasy burger,
  Hope this isn't hijacking your topic but it may be relevant

Doug,
  I've got two gensets, one in the house, one in the barn, each with independent grounds, but I ran a wire between the two so I can use the barn unit to power the house at times when I don't want the heat from the house unit. Should I bond the house and the barn? Disable the barn ground?       Bill

[xyzer]

Bill,
I know you asked Doug but my 2cents says the more ground rods the better. Our code out west here requires 2 ground rods 20 feet appart for each panel not in the same building or so many feet from the main panel. Or what they call a UFER. But anywho....ground rods are where loose trisity will go and in the summer with dry ground you might need all you got....and if you have a ground wire running between generators with a ground rod at each that would be good! the more the better in my book. All I really know if you have a problem you want mother earth to absorb it not you! Disclaimer: IDKS!
Dave

[Doug]

Sorry Bill I can't realy sugest anything for liability reasons and the fact I do not know your local codes.

Also and this is very import I am only liscenced as an electrician in Ontario with a 442A liscence. This means I do not wire homes or barns. My specialty is high voltage and industrial poly phase power. The rules governing what I do allow me to do things ( that become second nature ) and lead me to sugest things that are probably not acceptable to your local inspector.

Barns are intersting:
Some codes are farm specific when it comes to grounding and bonding in milking parlors for example.

And I don't think I ever have been in a real milking parlor ( Papas hobby farm and hand full of geese that chased me as a boy just don't count lol ).

Please call or drop buy your local utility inspection office with a box of doughnuts. Your local inspector is a lot more interested in not seeing you get hurt than he is in what permits you took out or who did the work. He can probably make some theorectical sugestions if you catch him a good day about a theoretical installation and it will all end there.........

[dkwflight]

Hi My 2cents
More grounds are better and the rest of the wireing needs to be correct as well

A fellow I knew many years ago has a dairy barn with some half a**d wiring and some stray voltage. He couldn't understand why his herd milk poundage was falling off. Big vet bills later and no improvement. He finally got zipped a little and found the short to ground. He got a pro to rewire the barn.
It seems the cows were getting a low voltage tickle that made them very unhappy.

My 20k ST head has a frame independant from the wires. It makes power without a grounded frame. No voltage to the ground from the frame.
Now I know you need a grounded frame, but while the wiring is good, no ground is needed except untill after the wiring develops a fault to the gen frame. Then you will get burnt, I think.
Dennis

[Doug]

Hi My 2cents
More grounds are better and the rest of the wireing needs to be correct as well

A fellow I knew many years ago has a dairy barn with some half a**d wiring and some stray voltage. He couldn't understand why his herd milk poundage was falling off. Big vet bills later and no improvement. He finally got zipped a little and found the short to ground. He got a pro to rewire the barn.
It seems the cows were getting a low voltage tickle that made them very unhappy.

My 20k ST head has a frame independant from the wires. It makes power without a grounded frame. No voltage to the ground from the frame.
Now I know you need a grounded frame, but while the wiring is good, no ground is needed except untill after the wiring develops a fault to the gen frame. Then you will get burnt, I think.
Dennis

There are 3 characteristics of an electric circut that aply to everything from Listeroid genset to the flight computer on a Soyuz spacecraft.
Resistance, Capacitance and Inductance.
Many a good wise man has been caught off guard with electricity because he forgot the potential of one of the three to come back and bite you.

You Ground once at the ground rod ( grid, plate ect aplication specific ) you bond all the non current carrying metal parts

The common or often refered to incorectly Neutral is also Bonded once in the building. Some places ( like secondary buildings fed from another location ) you may bond the common again or local codes may ask you to ground again. This is a very slipery slope and why I sugest you talk to people who are familiar with the codes in your area.

Dancing cows may be funny, but there are dead Menonites who tried to do it themselves in my area and got it wrong.

Sometimes more than one ground can create problems. I have some steel I beams with nastey ground current flowing threw them Induced from who knows what going who knows where. They actualy make arcs and sparks when you mess around with the armour on cables or try and attach a bond wire for something as simple light bulb in the boiler room.

But now I have 40 years of corroded grounds, rusty beams, fancy electronics and harmonics and literaly hundereds and thousands of miles f aroured cable and bonds and improvised grounds making all kinds of mischief. Don't create problems for yourself down the road by being creative.

[greasy_burger]

Ok, finally grounded the generator and wired it to a mini panel, I ran both 110 legs to the panel as well as the nuetral, but when I measure volatge I am getting 170 volts from 1 leg and 60 volts from the other but 118 volts at the receptacle I wired to one of the 15 amp breakers, can anyone tell me why I am not getting an even 110 volts from both legs?

[Doug]

That is interesting.

You are sure you have the neutral bonded to ground?

If you just bond the frame to ground then often you see wierd stuff like this ( since you would in effect still have an ungrounded system.

At your recepticals you have 118 volts between line and the common so that's right.

Do a continuity check between your common ( Neutral white wire ) and your ground and make sure there is a good connection ( not while runniong of course ).

You can also if you like check this by doing a voltage check on a running machine between the common and ground, there should be NO voltage ( maybe just some noise in the mili volt range ).

Please take some pictures of the all the wiring so I can see how you made your connection.

Doug   

[greasy_burger]

I remeasured at the panel and got a solid 240 volts so I guess all is well, My ground at the panel is grounded to the same rod that the gen head is grounded to, I will still take some pics tommorow and post for your approval/disapproval:)

[Doug]

You may not have a tie strap between the common bus or its not connected.

Do you have a meter check for a solid connection between ground and the common bus.

You should  with the unit off be able to read continuity to ground threw both lines and the common to ground if you don't your not grounded at all ( or something very strange on  ).....