Generator in a outside building and powering the panel...

[s219]

So tell me how do you manage interlocks and not have a condition where the generator can be connected direct to the utility

That's what the interlock prevents. I can't have both my back feed breaker and main breaker engaged at the same time. I have one of the simple interlocks that is designed and sold by GE for my GE panel. There are far more advanced types out there, off the shelf.

 

[milkman636]

From a practical standpoint the neutral and ground never get disconnected and are already adequately sized for the generator output. Plus the ground would be earth connected at the main panel. So they will work as the OP plans. So, is this a question of whether an inspector will buy into the plan?

 

[MossRoad]

Really, all you are wanting to do is put the generator in the barn and run a long extension cord from the genny to a breaker in your main panel that is interlocked, so that it cannot feed the main panel at the same time that the main power is on.

Your conduit is large enough.

You'll need a cable from the genny to an outlet (assuming you aren't hard wiring it).
An outlet.
A cable that runs from that outlet to the main panel in the house, NOT the sub panel in the garage.
A breaker in the main panel.
An interlock kit for that breaker in the main panel to select grid or genny power.

Don't try and be frugal and double purpose the ground and neutral for both functions. Why?
Because you'll confuse someone, somewhere, someday.

Don't run the wires for the genny through the sub-panel at all. Keep them seperate to avoid confusion.

Take a look at this schematic. It's probably similar to your current setup. Anyway, print it out and add in the genny circuit. Technically, I see no reason why you could not use the neutral and ground for both situations, as only the two hot legs are switched. I just would not do it because you'd have two wires running into the sub panel for the neutral and ground and two wires passing through the sub panel that do nothing. Keeping them seperate just makes more sense.

I have no idea if what you want to do would violate code or not. Running seperate would definately be up to code.

 

[MossRoad]

Thinking about it, all you are doing is saving the money on two lenths of wire. You still have to buy everything else. Its not that much money to do it with four wires instead of two. We know it will work with two, however, we still don't know if its legit to only use two. I guess that's a question for an electrical inspector. Glad we got that cleared up, eh??? :laughing:

 

[CobyRupert]

So tell me how do you manage interlocks and not have a condition where the generator can be connected direct to the utility ? -Kirk- key
The transfer switch has to either be at the utility pole and a pair of conduits run to and from the shed. Or the transfer switch mounted at the shed. With all the utility power being routed to the shed, through the transfer switch and back out a 2nd conduit to the utility pole. No transfer switch required. No new cables between main and sub-panel required.

Tell me why again this isn't an application for a kirk key. I didn't understand your explanation.

 

[radioman]

Reading this thread is making my head hurt. Mossroad is the only post that makes the most sense and its pretty much what I did. I put my portable genny in my new garage in back of house. I have a plug from genny to go into the outlet in the new garage feeding 220. I have the plug outlet hard wired to old garage going into the transfer switch that is right next to the main panel. I cherry picked circuits I wanted to be powered by genny and wired in extensions that is only on hot side to transfer switch box. The transfer switch box has the interlock on it so I can turn off the cherry picked circuits to be within the specs of the genny and still know if the power came back on the circuits I did not pick for the transfer switch. This is the ideal setup that I think everyone should follow.

I think azclan should be running complete seperate wires (2 hots,ground,neutral) to the house into the transfer switch from the barn genny plug box.

The question of the day is - is it code/legal to running separate circuit into the SAME conduit? suppose its permitted - what is his plan to pull new wires in the already fulled conduit ? The way I see it he would need to disconnect the wires from breaker in house completely, pull one of wires (preferably the ground wire) with a string attached to it and pull it out if it not tangled. if it is, he looking at pulling the whole shebang wires out and pull it back in with new circuit attached. something tells me this cant be code with two circuits. I am sure you can add another hot and use same ground/neutral for an extra circuit in same direction, but an opposite highway of power in same conduit for two different purposes? no. doesnt sound right. sorry guys.

I really think he should be running a new circuit in new conduit . He would have to dig holes on both side of driveway and tunnel/burrow a hole under the driveway with new conduit. I really dont think its a good idea try to save time thinking it will save money using the same conduit. Suppose it was done and op croaks? then someone else wants to expand/update etc and has bright idea to use the same wires. For all he knows without hiring a professional to trace the circuit underground its just extra wires to use in the future.

 

[buickanddeere]

It's more money that what it's worth compared to a proper reliance transfer switch. Plus somebody will eventually loose the key and there will be no power .
As previously stated the doubling of cables in the conduit requires de-rating.
Doing this job on the cheap is going cost more in the long run.
Just put a Champion 7200/7500 generator in a generator lean to beside the shed. Run a 8/3 cab tire cord from the generator to one of those reliance transfer switches. Be legal, safe and have something that anybody can operate. Instead of some farmer fix cob job that somebody will burn out if you are away or in the hospital when standby power is required.

 

[daybreak1998]

Tell me why again this isn't an application for a kirk key. I didn't understand your explanation.

Howdy,
Because he is trying to be cheap. Any custom kirk key setup would cost more than doing it correctly with all new wire pulls.

Pull new wires through the conduit, and terminate with generator receptacle. A complete simple homerun back to the main panel with the interlock and dual pole 50 amp breaker.

done, functions correctly, and can be used safely.

 

[CobyRupert]

I see that a Kirk key lock is about $40 x2 locations = $80 and about 10 minutes of fastening. Don't think you can by a transfer switch and new cables from main panel (or transfer switch) to sub (or genny) for that. Plus pulling new cables into an existing used conduit and installing a transfer switch is going to take a whole lot of time and require utility power being turned off.
But whatever.....

 

[BX23D]

Really, all you are wanting to do is put the generator in the barn and run a long extension cord from the genny to a breaker in your main panel that is interlocked, so that it cannot feed the main panel at the same time that the main power is on.

Your conduit is large enough.

You'll need a cable from the genny to an outlet (assuming you aren't hard wiring it).
An outlet.
A cable that runs from that outlet to the main panel in the house, NOT the sub panel in the garage.
A breaker in the main panel.
An interlock kit for that breaker in the main panel to select grid or genny power.

Don't try and be frugal and double purpose the ground and neutral for both functions. Why?
Because you'll confuse someone, somewhere, someday.

Don't run the wires for the genny through the sub-panel at all. Keep them seperate to avoid confusion.

Take a look at this schematic. It's probably similar to your current setup. Anyway, print it out and add in the genny circuit. Technically, I see no reason why you could not use the neutral and ground for both situations, as only the two hot legs are switched. I just would not do it because you'd have two wires running into the sub panel for the neutral and ground and two wires passing through the sub panel that do nothing. Keeping them seperate just makes more sense.

I have no idea if what you want to do would violate code or not. Running seperate would definately be up to code.

In Ontario Canada this is not legal. A power supply line needs to be in a separate conduit from a feed line. Four conductor wire will be needed. Any wire, even in a conduit needs to be underground cable. The transfer switch uses all 4 wires and transfers the bonding to the generator. Make sure the generator is set to bonded mode. The cable depth is also regulated and if under a driveway needs further protection.
The bonding must be at the power source, main panel when fed from the utility and at the generator when powered from the generator. Do it right, and do it once. Don't forget to have it inspected.