Generator supplying multiple panels (not typical)

[bollpie20]

this is my first post and have been impressed by the level of knowledge here, so I appreciate any help with this!!

I will try to explain my set up currently and the direction I’d like to go…if possible! I’m not an electrician, so I will do my best explaining, but I apologize in advance

Currently my home has a CT cabinet indoor which then feeds (2) 200 amp panels. Off of the 2nd 200 amp panel is where my current generator is “fed” from with 8-10 different circuits on the transfer switch.

I’m in the process of building a barn (36x72 footprint with a basement, garage, & living space levels)

After a few months of waiting, the power company said I could splice at the CT cabinet in order to run a service line to the new barn which will be another 200 amp panel. I originally thought I needed to place another service and meter on the new barn but was given the option to do it this way which saves a ton of money and work on my end!

My question is while doing this, I thought to upgrade the generator to a 30-36 kw and provide emergency power to all (3) 200 amp panels if it would be possible. Is this possible?? I’ve attached pictures of the current set up should what I’m saying be somewhat confusing

 

[theoldwizard1]

My question is while doing this, I thought to upgrade the generator to a 30-36 kw and provide emergency power to all (3) 200 amp panels if it would be possible. Is this possible?? I’ve attached pictures of the current set up should what I’m saying be somewhat confusing

In this day and age, almost ANYTHING is possible given enough time and money !

Very few companies would require 30+ kw if backup power. To run that, you would need a very large V12 or V16 engine. It had better be natural gas because running something like that would require more than 1000 gallons of diesel storage. Even then, it might only last a few days and could you get that refilled during an emergency ?

 

[nadogail]

How much money do you have to feed this project? That will be the limiting factor. You might prioritize your loads so they can share your generator capacity. Rather than buy three transfer switches, I suggest you install interlocks on two panels; identify and label the breakers feeding your higher priority loads to enable you to select where your power will be sent.

 

[wyliesdiesels]

The easiest way to do this would be interlocks on all 3 panels.

You obviously cant feed the CT cabinet

Otherwise, if you want an ATS you would have to put the ATS in between the CT cab and 3 panels. Then the 3 panels have to be converted to subpanels

 

[Bert_]

In this day and age, almost ANYTHING is possible given enough time and money !

Very few companies would require 30+ kw if backup power. To run that, you would need a very large V12 or V16 engine. It had better be natural gas because running something like that would require more than 1000 gallons of diesel storage. Even then, it might only last a few days and could you get that refilled during an emergency ?

Dude, you are clueless. 30kw generators usually run a 4 cylinder diesel or 6 cylinder propane/gas.

We have no idea what is or isn't overkill since we don't know his loads.

 

[wyliesdiesels]

In this day and age, almost ANYTHING is possible given enough time and money !

Very few companies would require 30+ kw if backup power. To run that, you would need a very large V12 or V16 engine. It had better be natural gas because running something like that would require more than 1000 gallons of diesel storage. Even then, it might only last a few days and could you get that refilled during an emergency ?

Are you sure?

This one is powered by a 4cyl.

You must be stuck in the 80s

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[theoldwizard1]

Are you sure?

This one is powered by a 4cyl.

You must be stuck in the 80s

Certainly the 90s l

 

[bollpie20]

The easiest way to do this would be interlocks on all 3 panels.

You obviously cant feed the CT cabinet

Otherwise, if you want an ATS you would have to put the ATS in between the CT cab and 3 panels. Then the 3 panels have to be converted to subpanels

Thank you for this…this is helpful!

 

[bollpie20]

How much money do you have to feed this project? That will be the limiting factor. You might prioritize your loads so they can share your generator capacity. Rather than buy three transfer switches, I suggest you install interlocks on two panels; identify and label the breakers feeding your higher priority loads to enable you to select where your power will be sent.

This is a good way to think about it…maybe the easiest thing to do is placing all the “important circuits “ into one panel and have just one panel on a transfer switch…thank you!!

 

[dcg9381]

I feed several panels, to do that I put an ATS up front (as Wylie mentioned).
I also added two "load shed" modules (they come in 50A and 100A) - SMM modules to make sure that my ACs and one sub-panel do not turn on at the same time. These modules are simple "timers" that work by delaying the circuit going hot once power is lost. You set a variable delay in each one. The modules can also detect under-frequency (generator RPM dropping) to detect overload conditions. They operate on their own and do not need to have wired control to the generator.

 

[Stuart in MN]

The term 'emergency power' usually means only the circuits that are absolutely needed in an emergency situation...heat or a/c (depending on your location), a well, a few lights and outlets, that sort of thing. Will having power to this new barn be necessary if there's an outage?

 

[Steve from Socal]

In this day and age, almost ANYTHING is possible given enough time and money !

Very few companies would require 30+ kw if backup power. To run that, you would need a very large V12 or V16 engine. It had better be natural gas because running something like that would require more than 1000 gallons of diesel storage. Even then, it might only last a few days and could you get that refilled during an emergency ?

Are you missing a zero or two in your prime mover size? Even in the 60's and earlier 30 KW generators used small engines,30 KW electric is 40 HP so a 55/60HP engine is the size needed. That 30KW is 250 amps at 120 volts or 125 amps to three sub panels feed 240. The sweet spot for a gen set is 75~80% so it is right at 100 amps to feed three panels, that sounds about right for back up power from here?

To the OP, IF you do need a good back up look for a gen set that is rated for "prime power" they are more resilient than back up rated units. That sweet spot is important for all generators but particularly diesel power where low load factors are not good.

Steve

 

[jpcjguy]

I have two 200A panels in my house. One panel as a 120A breaker running to the detached garage. I put interlocks on both house panels and wired a generator outlet that feeds both panels (interlock breakers - 30A). I have 13k starting 8k running generator that feeds all three panels and I just know to turn off the HVAC, water heater, oven and anything else I don't need/want. This then gives me access to all the lights and outlets in the house and garage that I want to use. I can also selectively shut down those lights and outlets that I want also.