Stand by generator

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JDB3

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San Antonio, Texas
A "friend of a friend" of mine has a house that is in the finishing stages (being painted). Another company has wired it (it was to big & design bad for wiring) & does not want to do a back up generator. :huh:

Stand alone 4 guest quarters, main house with high & vaulted ceilings, stand alone structure with walk-in cooler, walk-in gun safe, laundry room, etc.

It has around 4 sub-panels feed by 2 outside sub-panels that are feed by main disconnect (underground) from service pole. I think the service is 400 amp single phase! :slaphead:

Is there a way now, to turn select breakers off remotely (so that the generator would not have to carry entire load) ?

I will post more once I meet with owner to find out what he would like to feed with this generator. I know that there are smart people out there! Thanks.
 
}}templdl Do they have to be turned on again remotely? {{

I do not think so. He would just be glad to have the generator control certain circuits (without creating parch work).
 
JDB3 said:
}}templdl Do they have to be turned on again remotely? {{

I do not think so. He would just be glad to have the generator control certain circuits (without creating parch work).
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Tell him to pick out the circuits he wants on the genset and move them to their own panel with a transfer switch
between the feed to the panel and the panel.
Automatic transfer switch or manual transfer switch will work this way. Just make sure genset will carry the load transferred to it by the transfer switch if he goes with automatic.
 
JDB3 said:
}}templdl Do they have to be turned on again remotely? {{

I do not think so. He would just be glad to have the generator control certain circuits (without creating parch work).
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Then a simple shut trip would work. The next issue is if the panels have main breakers as they may be large enough to specify a ST as an option.
But, I may assume that you are looking for the ability to shed individual branch breaker loads. If so beakers are available with a shunt trip option but breads such as the C-H CH breakers require an extra space for the ST with each breakers.
Also check out the C-H lighting control system which uses solinoid operated breakers type GHBS. Controled and non controlled breakers can be mixed in the panel. If I can recall all are 1" per pole.
 
JDB3 said:
He would just be glad to have the generator control certain circuits (without creating parch work).
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Is he willing to use a completely manual setup? If so a generator with an inlet box and a main breaker interlock would allow him to choose any circuit.
 
}} infinity
Is he willing to use a completely manual setup? If so a generator with an inlet box and a main breaker interlock would allow him to choose any circuit{{{

He has a ranch foreman (they breed & raise white tail deer as well as have horses & cattle) so someone is normally around. So completely manual would probably work.

When you mention "a generator with an inlet box" and "a main breaker interlock", I am not certain what that means? Been a while since I have done a generator, & then I knew in advance about the customer wanting one, so I could wire accordingly.

Thanks for all the feed back! :happyyes:
 
JDB3 said:
}} infinity

When you mention "a generator with an inlet box" and "a main breaker interlock", I am not certain what that means? Been a while since I have done a generator, & then I knew in advance about the customer wanting one, so I could wire accordingly.

Thanks for all the feed back! :happyyes:
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These are interlocks: http://natramelec.com/ keep in mind they are not ul listed but I have used them and they work well.

These are generator inlets: http://www.lowes.com/Search=generat...wSearch=true&Ntt=generator+power+inlet+boxes#!
 
The Eaton Pow-R Command system is expensive; designed predominantly for commercial buildings. Probably not a realistic option.

Somehow you have to figure out how to isolate the circuits you want to keep running, then be able to feed them by alternate sources, ATS probably the best. That way you can feed the isolated circuits from either source automatically or manually, and even if power returns the gen could keep running and feed those loads.

One method could be to put the isolated circuits on two contactors with line sides connected to each of the sources, and outputs tied together (load side), and then use a manual source selector switch to control the contactor coil voltages to energize either the normal source contactor or gen source contactor, but not both.
 
I do not think that a purely electrical design (e.g. interlocked contactor coil feeds) meets the requirements for a TS. Relay failure or manually pushing a contactor armature would defeat any protection.
 
GoldDigger said:
I do not think that a purely electrical design (e.g. interlocked contactor coil feeds) meets the requirements for a TS.
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I agree as every listed transfer switch I have worked on has mechanical means to prevent connection of both sources.


Hmm, as I typed that I realized I have never worked on a closed transition transfer-switch and those do connect both sources at once. :?
 
Using a manual source selector switch for coil energization would not allow for paralleling. It would be physically impossible to energize both coils at the same time through the switch, without some type of intervention; advised or ill-advised.

I'm sure it would be possible to defeat just about any control scheme, but how many contingencies do you build into the equipment? Improperly operating the equipment is way outside NEC, or AHJ.
 
Either a handle interlock or armature interlock will not be compromised by a switch failure. A coil switch just does not seem to me to have that same degree of certainty.
 
qcroanoke said:
These are interlocks: http://natramelec.com/ keep in mind they are not ul listed but I have used them and they work well.

These are generator inlets: http://www.lowes.com/Search=generat...wSearch=true&Ntt=generator+power+inlet+boxes#!
Click to expand...
I have used many of them also. The only problem here is if he has a 400amp service the 400amp services residential I have done were double lugs in the meter and two 200amp panels. Too bad they didn't plan ahead and could have made one panel for either manuel or automatic generator.
 
}}I have used many of them also. The only problem here is if he has a 400amp service the 400amp services residential I have done were double lugs in the meter and two 200amp panels. Too bad they didn't plan ahead and could have made one panel for either manuel or automatic generator.{{

Yep, it would have been nice. :D One salesman, has pretty well said that about the only way to do it, is manually. Select circuits they would like running, turn others off, & manually operate the generator & manual transfer switch.

Owner has decided to wait till all others are completed with their work, then do the generator. That way we can also see just what size will be needed.

What do you'll think: :? Might need 2 transfer switches if there are parallel feeds to the trough, that then goes to the 2 200 amp outdoor panels that feed 3 indoor panels ? :?
 
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