8 kw Generac generator

[codeunderstanding]

I have a installation question. I am wiring a air cooled generator to a house with a few selected critical loads. The service for the house is a 200 amp service with a 150amp subpanel also next to the 200.

Some of the critical circuits are in the 200 and some in the 150. I was thinking about using the prepackaged transfer switch but got to thinking that may not be the best set up because the 2 foot whip would only go to one of the panels.

So what do some of you guys wire these up with circuits in both panels?

 

[Robert Hutcherson]

I would install (1) 200amp manual transfer switch ahead of the 200amp panel/main. This would allow more flexible control of any of the circuits to the house. It would be safe as long as you did not exceed the capacity of the generator. Good luck.

 

[tom baker]

I would install (1) 200amp manual transfer switch ahead of the 200amp panel/main. This would allow more flexible control of any of the circuits to the house. It would be safe as long as you did not exceed the capacity of the generator. Good luck.

The 2008 NEC, for this application, would required the generator to be able to carry the calculated load connected, and may require a large generator, and is a very expensive retrofit.
The posters method could result in a small, 10kW generator.
What I would do is intstall a small 12 ckt feeder panel, with a pair of interlocked circuit breakers as a MTS. The feeder panel is fed from generator and has the critical circuits

 

[codeunderstanding]

The 2008 NEC, for this application, would required the generator to be able to carry the calculated load connected, and may require a large generator, and is a very expensive retrofit.
The posters method could result in a small, 10kW generator.
What I would do is intstall a small 12 ckt feeder panel, with a pair of interlocked circuit breakers as a MTS. The feeder panel is fed from generator and has the critical circuits

Thats kind of how I think I will do it. Only this will be with a automatic transfer switch and i will set a nother small panel for his circuits he wants to use.

 

[WinZip]

I would set a trough under both panels an take circuits from each panel to the trough , then drop down to a generator sub panel then of course the transfer switch is ahead of the sub panel , unless you can drop the circuits out of each panel to sub panel without a trough.

 

[codeunderstanding]

I would set a trough under both panels an take circuits from each panel to the trough , then drop down to a generator sub panel then of course the transfer switch is ahead of the sub panel , unless you can drop the circuits out of each panel to sub panel without a trough.

Thats exactly how I have it drawn out. I guess I do know some what that I am doing.

 

[WinZip]

It can be difficult at times to drop those circuits from two panel's an get to the sub panel.

 

[qcroanoke]

The 2008 NEC, for this application, would required the generator to be able to carry the calculated load connected, and may require a large generator, and is a very expensive retrofit.
The posters method could result in a small, 10kW generator.
What I would do is intstall a small 12 ckt feeder panel, with a pair of interlocked circuit breakers as a MTS. The feeder panel is fed from generator and has the critical circuits

Only if it is a automatic transfer switch.
Manual transfer switch does not require the generator to be large enough to carry the transfered load.
Don't have my code book so I can't quote chapter and verse......

 

[ceb58]

I have a installation question. I am wiring a air cooled generator to a house with a few selected critical loads. The service for the house is a 200 amp service with a 150amp subpanel also next to the 200.

Some of the critical circuits are in the 200 and some in the 150. I was thinking about using the prepackaged transfer switch but got to thinking that may not be the best set up because the 2 foot whip would only go to one of the panels.

So what do some of you guys wire these up with circuits in both panels?

Are you talking about the type ATS that is a 12 or 16 circ. panel? If it is then do as you thought. Set a trough to drop the critical circ. from the two panels into it to run to the ATS.

 

[stew]

not sure why you need a trough for this. the 12 or 16 circuit panel becomes you new sub panel.(I am assumining you will use the 12 or 16 circuit automatic transfer switch that generac makes for this genrator) It can be fed by a breaker in the 200 amp panel. Simply run the critical branch circuits to the new sub and you are in business. Use the 200 amp panel or the old sub as a chase if you need to. all perfictly legit as long as the generator is sized for the load. See702.5(2) a

 

[codeunderstanding]

not sure why you need a trough for this. the 12 or 16 circuit panel becomes you new sub panel.(I am assumining you will use the 12 or 16 circuit automatic transfer switch that generac makes for this genrator) It can be fed by a breaker in the 200 amp panel. Simply run the critical branch circuits to the new sub and you are in business. Use the 200 amp panel or the old sub as a chase if you need to. all perfictly legit as long as the generator is sized for the load. See702.5(2) a

I would like to use the prepackaged sub that they make, but the generator is going to have to be set back 20' from the house. Then where I would stub in the house with the whips its another 50' to the panels. I'm probly better using my own critical panel than extending generacs panel

 

[Jim W in Tampa]

8 KW is not large enough to carry much. Not sure that automatic transfer will work very well.
But if they dont want manuel transfer then i would move the circuits needed to a sub panel . That would lower the cost of the switch as your not needing 200 or even 150 amps

My own is on manuel and i can select almost any load but limited to 5500 watts.
Will this gen be diesal, gas or LP ?
I converted my gas gen to LP makes life easy.

 

[codeunderstanding]

8 KW is not large enough to carry much. Not sure that automatic transfer will work very well.
But if they dont want manuel transfer then i would move the circuits needed to a sub panel . That would lower the cost of the switch as your not needing 200 or even 150 amps

My own is on manuel and i can select almost any load but limited to 5500 watts.
Will this gen be diesal, gas or LP ?
I converted my gas gen to LP makes life easy.

This would be natural gas. From what this customer want to use I only came up with 4500 watts.

well
sewer lift pump
2 refrigerators
one bedroom office

 

[Jim W in Tampa]

This would be natural gas. From what this customer want to use I only came up with 4500 watts.

well
sewer lift pump
2 refrigerators
one bedroom office

Then it should work as long as only those loads would transfer.

 

[ceb58]

I would like to use the prepackaged sub that they make, but the generator is going to have to be set back 20' from the house. Then where I would stub in the house with the whips its another 50' to the panels. I'm probly better using my own critical panel than extending generacs panel

Just dont forget about 225.31,225.32 and 445.18

 

[roger]

This would be natural gas. From what this customer want to use I only came up with 4500 watts.

well
sewer lift pump
2 refrigerators
one bedroom office

If your pumps and refrigerators have the potential to start at the same time the 8KW will probably not do it.

I would contact the generator manufacturer and run it by them.

Roger

 

[hillbilly1]

If your pumps and refrigerators have the potential to start at the same time the 8KW will probably not do it.

I would contact the generator manufacturer and run it by them.

Roger

I wouldn't totally bank on the manufacture giving good info either, when we were installing them for the orange box, Generac had reps at the stores occasionally, and they would tell the customers their generators would run the moon! I had several angry customers when they found out they wouldn't run what they said they would. I had one customer that I temporarily connected the A/C unit to the generator to show him it wouldn't pull it. After about a minute of the compressor whining trying to start, he believed me.