1200 Amp MCB And 130kW Generator

[hillbilly1]

The start contact on two wires, are dry contacts, so you can parallel as many as you want. The control voltage comes from the generator.

 

[Seven-Delta-FortyOne]

When I have put two ATSs on a Generac, the instructions showed how to wire them as a master/slave pair.

Found it. It’s in one of the courses I’m doing.

N1, N2, and T1 are only run to the gen from one ATS.

23, 94, and 0 are paralleled between the two ATSs.

Not sure where the relay would come into play

As far as the 130, I don’t even know if it’s 2 wire or 6 wire.

 

[Birken Vogt]

All of the big Generacs can be set up 2 wire start like anything else.

But based off the questions you have been asking, I suggest you get a generator place involved, rather than just going to a catalog.

There is more to it than, the cheapest generator that will get you 130 or whatever kw you want. Who is going to service it going forward and are they any good at servicing the product would be question #1.

 

[Seven-Delta-FortyOne]

There is more to it than, the cheapest generator that will get you 130 or whatever kw you want. Who is going to service it going forward and are they any good at servicing the product would be question #1.

Not in my SOW.

Like at said at the beginning, they already have a 130kW, and two ATS.

They want either that unit or a larger one, and they want the entire facility powered.

When I go look at the job, I’ll know if it’s 2 wire or 6 wire, how it’s configured, what the switch gear is like, etc.

I merely wanted to get a little extra info from folks who’ve done this before.

Im a Generac Factory Authorized Installer, I’m in the process of getting more training from Generac on the industrial line, I work with planners and EEs, and I don’t consider a forum, no matter how good, a substitute for professional training and/or design services.

It is unlikely that I’m going to plunge head first into something that is far beyond my ability, and cause irreparable harm.

But I will continue to study and train, and even chat with other technicians, and expand my company any into other areas that interest me.

 

[Birken Vogt]

Apologies for not having paid attention to all the facts in this case.

Nevertheless, all generators of this size should be able to do 2 wire start. If it is a true industrial unit, it may be that the Generac house is the only one that can ever have the keys to work on it, and the customer may be out of luck and have to pay whatever they ask. That's how it is in my territory.

Looking at the standard commercial line, I don't see any transfer switches over 800 amps, so you probably have to go to the industrial dealer to buy a 1600 amp version, and then you will be locked into their service forever. So it probably makes more sense to go with ASCO whatever you decide to do.

 

[electrofelon]

OP needs to figure out the load, but I'm guessing 1200 A is way overkill.

 

[Seven-Delta-FortyOne]

OP needs to figure out the load, but I'm guessing 1200 A is way overkill.

They have hired me to perform a load Calc.

But regardless of the actual load, if it has a 1200A main, then a single transfer switch will need to be a 1200A.

And there are 8, 200 amp subs, so regardless of actual usage, separate transfer switches to power the entire facility will have to be 200A switches.

 

[hillbilly1]

They have hired me to perform a load Calc.

But regardless of the actual load, if it has a 1200A main, then a single transfer switch will need to be a 1200A.

And there are 8, 200 amp subs, so regardless of actual usage, separate transfer switches to power the entire facility will have to be 200A switches.

Yes and no, if you use a service rated transferswitch, it can have a lower rating, such as 800 amps, the 1200 amp can remain. Another issue if you go with a bigger generator and 8 transfer switches, you will need a distribution panel off the generator feed.

 

[Seven-Delta-FortyOne]

Apologies for not having paid attention to all the facts in this case.

Nevertheless, all generators of this size should be able to do 2 wire start. If it is a true industrial unit, it may be that the Generac house is the only one that can ever have the keys to work on it, and the customer may be out of luck and have to pay whatever they ask. That's how it is in my territory.

Looking at the standard commercial line, I don't see any transfer switches over 800 amps, so you probably have to go to the industrial dealer to buy a 1600 amp version, and then you will be locked into their service forever. So it probably makes more sense to go with ASCO whatever you decide to do.

Pretty rural area here in Humboldt.

Theres a couple of authorized repair companies, that also sell the units. But they are not Licensed Electrical Contractors, so they can’t install.

Then there are places like Platt who are dealers, but don’t do any service.

And all the installations are done by ECs like myself. Some of us have gone and gotten factory trained, most have not.

And the particular outfit I’m dealing with is a tribe, and without getting to deep into it, they have a, uh, unconventional way of doing things. They are not even required to get county or State permits for anything, so figuring out what has been done before, and how, adds another layer of complexity.

 

[electrofelon]

They have hired me to perform a load Calc.

But regardless of the actual load, if it has a 1200A main, then a single transfer switch will need to be a 1200A.

And there are 8, 200 amp subs, so regardless of actual usage, separate transfer switches to power the entire facility will have to be 200A switches.

Not really. For the case of a a non-service rated transfer switch, you could downsize that 1200 main to something smaller. But note you might not even need to do that. There is no requirement that a switch be protected at its rating by an ocpd. What you will have to do is meet the withstand and sccr ratings of the switch. The manufacturer will give you a chart of different breakers with different ratings and they typically allow you to have a bigger breaker than the switch rating in some cases.

 

[Seven-Delta-FortyOne]

Yes and no, if you use a service rated transferswitch, it can have a lower rating, such as 800 amps, the 1200 amp can remain. Another issue if you go with a bigger generator and 8 transfer switches, you will need a distribution panel off the generator feed.

If I went the 8 separate route, I was planning to use a can, and install terminal blocks inside, and make use of tap rules to feed the ATSs.

 

[Seven-Delta-FortyOne]

Thanks for that guys. Brain fart on my end.

If it calcs out, maybe I can just do a single 800.

Platt is so far not having success finding me a 1200, even though Generac has spec sheets for them.

 

[electrofelon]

If I went the 8 separate route, I was planning to use a can, and install terminal blocks inside, and make use of tap rules to feed the ATSs.

Until you know loads, it's all guess work. Like I said, I've got a 600 xfer switch that has like 8 200A panels and 5 100 A panels spread across 3 buildings, and load is only about 320A. Just saying loads could be a lot less than you think.

 

[hillbilly1]

If I went the 8 separate route, I was planning to use a can, and install terminal blocks inside, and make use of tap rules to feed the ATSs.

Hope for a big electrical room! LOL!

 

[Birken Vogt]

I am working with a customer on a building right now that has 9, 480V, 100 or 200A services grouped, with a 1000 or 1200A pre-meter switch, although they occupy the whole building as one. Was once set up for tenants. They are running a huge laser cutter, press brakes, and have some huge AC planned in the future, nevertheless you could almost run the whole building off a single 200A 480V service from our observations.

 

[Birken Vogt]

Also I am curious, I don't know if you have specified if this is a standard or industrial generator, does it communicate with the existing transfer switches with RS485 or regular 2 wire start or DC from the controller like small residential.

There is a Generac place listed on the industrial dealer locator just east of Redding that looks like an independent, wondering if they could be any help on this.

 

[electrofelon]

I am working with a customer on a building right now that has 9, 480V, 100 or 200A services grouped, with a 1000 or 1200A pre-meter switch, although they occupy the whole building as one. Was once set up for tenants. They are running a huge laser cutter, press brakes, and have some huge AC planned in the future, nevertheless you could almost run the whole building off a single 200A 480V service from our observations.

If I may nitpick your wording: you have one service. You have 9 meters.

 

[Birken Vogt]

If I may nitpick your wording: you have one service. You have 9 meters.

Correct you are. Never thought of it that way I guess.