Essential system with 100% building generator back up

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wipeflusher

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Essexville, Michigan USA
Greetings to all. My first time here, so I'll try to be articulate:
I work at a skilled nursing care facility. My service to the facility is 480v, 800 amps. Before I got here, there was one 250kva generator supplying the Essential system power to the building. Since that time, we have replaced that with 2) 500kva generators, and also added a separate (fourth) transfer switch that connects "Normal Power" to the generator back up. So, I now have 100% of the building backed up on generator power. (the normal power xfer switch is time delayed 10 seconds).
I'm wanting to re-do power to our Laundry facility, which the equipment (washers, dryers, linen folders, etc.) has been, and still is on the Equipment branch of the Essential Systems. I was hoping to supply a new 480 volt feeder from the Normal Power switchgear to the Laundry Room, transform it down to 208/120v and transfer the existing branch circuits from an old panel to a new one located in another area of the Laundry Room. I asked my electrical engineer (we're doing an extensive remodeling project) if I could take that feeder load OFF of the Equipment branch and feed it through Normal Power now, since the building is now basically 100% backed up. Even though he didn't have anything to back up his opinion, he thought we should leave it on the Equipment branch.
I know that NEC 517.34(B) contains a list of specific equipment permitted to be connected to the equipment system (item 8), referring to non-specific and generalized, where 517.30 (B)(5) requires equipment to be specifically named and served by their own transfer switches. If you get into NFPA 99 (Health Care Facilities), Section 3.4.2.2.3 (e), the appendix has this commentary:
"Consideration should be given to selected equipment in kitchens, laundries, and radiology rooms and to selected central refrigeration." It goes on to address handling heavy loads, etc.
In essence, there's a lot in the codes talking about what ADDITIONAL loads COULD be added to the Equipment branch, but again, we're talking about a facility that only has generator back up on the Essential system and not the entire building like we are now. A lot of focus is on making sure this extra equipment is on an additional transfer device. I see the new Normal Power Transfer Switch we installed as such an additional device. How do I address code adherence to a building that's 100% backed up?
 
wipeflusher said:
How do I address code adherence to a building that's 100% backed up?
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I think that is your actual question. Could you explain the details of your concern?

While I don't see any reason that you would have to transfer optional equipment from the Equipment Branch to the normal system, you could. It is an expense that should have a purpose.
 
wipeflusher said:
Hmm...did I make my first ever question too difficult? Or is this just a grey area no code addresses? Is having a fully backed up building a rarity?
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No offense, but it was a little long to read. And I'm not 100% I understand what the question was, but this is kind of what I got:

You have a building that is 100% backed up with what I'll call an optional transfer switch. And you want to know if you should keep the separate equipment branch transfer switch, or put the entire building on the optional switch? Is that right?

I think code would allow either, and its basically your call. Do the two switches give you better reliability? If one shot craps, part of the building would still have power? Or would you prefer to eliminate the testing & maintenance associated with an extra switch?

I'm sure there are other advantages and disadvantages, but I think you should weight those.
 
Yeah, I was a tad wordy.

Let me try to simplify......... It's a care facility. Before we installed the new 2 generators, there was just one small generator that only backed up Essential System power. Each of the three branches (Life Safety, Critical Power, Equipment) had their own transfer switch. Everything else (Normal Power) had no generator back-up.
Back then, the Laundry equipment was put on the Equipment branch. All I want to know is, am I required by any code to keep Laundry equipment on the Equipment branch, or can I now feed it from the Normal Power switchgear?
Now with the new generators, absolutely everything in the entire building is backed up by the new generators.
 
wipeflusher said:
All I want to know is, am I required by any code to keep Laundry equipment on the Equipment branch, or can I now feed it from the Normal Power switchgear?
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What code ever required your laundry equipment to be backed up by a generator? Doesn't you state health care regulatory entity require you to have a back up of bed and patient wear?

Roger
 
am I required by any code to keep Laundry equipment on the Equipment branch, or can I now feed it from the Normal Power switchgear?
Now with the new generators, absolutely everything in the entire building is backed up by the new generators.[/QUOTE]

i can't think of another place to look, what is the load on the laundry circuit, i assume the normal power time delayed can safely carry the Laundry equipment load.

are your generators ganged through the mains transfer switch?
'
 
I don't think I'm required to, either. The way I read NFPA 70, 517(B)(5) prohibits loads from being placed on the Equipment branch unless specifically named. Those loads I see in 517.32 through 517.34. However, these are permitted loads, and not required. Any other loads than these could still go on the Equipment branch, but they have to be served by their own transfer switch so the generating equipment isn't overloaded. These are generalized,non-specific equipment or loads and aren't named.
So, how I see it, if a load isn't specifically named in 517, it doesn't have to be on the Equipment branch. Laundry loads aren't mentioned in NFPA 70.
Now, NFPA 99, (Standards for Health Care Facilities) recommends Laundry loads, as well as other unnamed loads to be put on the Equipment branch in an appendix commentary:
"Consideration should be given to selected equipment in kitchens, laundries, and radiology rooms, and to selected central refrigeration.
It is desirable that, where heavy interruption currents can be anticipated, the transfer load be reduced by the use of multiple transfer devices. Elevator feeders, for instance, might be less hazardous to electrical continuity if they are fed through an individual transfer device" Maybe this is what my electrical engineer is thinking of.
All of the remaining, "non-essential" power in my building is now on what we call the new "Normal Power" transfer switch. Engineers have tested both new generators and guarantee that the entire building load (including Essential systems) can be handled by just one of the two generators. So, I can't see anything that would prohibit me from moving the Laundry loads to Normal Power. I guess I should email this to my electrical engineer. Unless I'm missing something.
 
Assuming it was never required to be backed up (that's what I was assuming before), I still believe it could go on either normal or equipment.
 
Personally I would keep the 3 branches of the emg. System as clean as possible. I think we know the intent of the code is to keep the gen-set from being overloaded and having the ability to shed equip loads if it became necessary. Having a back-up system that can handle the entire facility is fantastic. I mantained a hospital system for over 20 yrs and always wanted bigger generators. When a tragedy happens you never know what context it is going to present you with. If for whatever reason your equipment fails and you are scrambling to get power from a rental or some other source you need to be able to re-energize critical and life safety loads first and foremost. Being able to hit those transfer switches with power quickly is more important, then you can worry about equipment loads. That has been my experience.
 
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