planned maintenance on hospital generators

[mshields]

When a hospital needs to disable their generator (assuming they only have one) for routine maintenance, they typically let all key personnel the in hospital know about it such that no procedures are performed during that time AND they bring in a temporary unit since no matter what they always have patients relying on the EES. I believe that the temp generator needs to be fully sized for the entire EES. Am I correct about that?

Someone recently suggested to me that all they need to have covered is the "Emergency" system. Of course, hospitals no longer have "Emergency" systems but lets say he's talking about what used to constitute the Emergency system, namely LS and C.

My response was that the hospital does not have a Standby Generator with optional loads on one of the ATS's, it has an Essential Electrical System where everything on it is indeed regarded by the code as Essential.

Do you agree or are their provisions perhaps limited to short duration standard maintenance that provides any kind of exceptions. I wouldn't think so, since making exceptions to something that is essential strikes me as counterintuitive.

Still, what do you think?

Thanks,

Mike

 

[GoldDigger]

It seems to me that you have analyzed it well, but it is out of my area of expertise.
There may also be relevant requirements on the temp standby generator contained in codes other than the NEC.

 

[publicgood]

To maintain normal occupancy, the full capacity of the essential system should be provided via temporary power. Redundant generation my be disregarded. See NEC 590.

 

[Ingenieur]

does any code require electrical provisions be made for this scenario?

eg a manual xfer switch
input 1 permanent genset NC
input 2 temp genset NO
output to permanent ats genset input

 

[jcassity]

your splitting hairs that equal expense.

you see there is a dedicated electrical system to be used for emergency circuits.

in many critical facility cases a genset is sized to handle the whole faclity ,, everything....... but when crap hits the fan like they are running low on fuel or something , the customer (hospital) can eliminate non-essential circuits to extend the fuel run time., sometimes the gen is only sized to back up just bare bones essential ckts.

the faclity should have an MTS avalable to you to hook up a roll up gen and i bet they are asking you to match the existing gen size as the temp gen...

If you can back up the essential circuits only, they probably dont want the interruptions that would cause on the non-essential areas.

This probabably has more to do with the scope of work you quoted and thier asking you to provide more than it does about the NEC. besides, if you open up and read the NEC introduction , scope of work and the exemptions, you might be surprised to see them being exempt, yet try telling the insurance company that ... LOL

I have found its much less expensive to parallel in smaller gens that add up to the "overall need" as the "roll up" than to match the existing.

thier actual loads during normal operating conditions to cover everything "on" might be thier target desire yet you may not have quoted that. If you amp clamp them today , you may discover that even though they have a 1.5mw gen,, thier load now with all hvac,, everything is only at 720kw. Negotiate a stratigic non essential HVAC unit or two thats not really needed during your maint window and you might find you can make them happy and maybe win another later, treating this as a cup half full lesson learned.

 

[steve66]

So you are asking if its required to provide backup power for the equipment systems during a planned generator maintenance interval?

I'd say it depends on the exact load. I don't see any reason you would have to backup heating and cooling systems, if the building temp. can be reasonably maintained during the outage.

But if its med gas systems, which someone's life might depend on, then yes, you need backup.

I believe the 2017 has some requirements about having a way to connect temp. generators during maintenance and during other planned generator outages.

 

[kwired]

I'd say it depends on the exact load. I don't see any reason you would have to backup heating and cooling systems, if the building temp. can be reasonably maintained during the outage.
.

Seems reasonable that if the down time duration is going to be short, some things like heating and cooling systems could be allowed to be off during that time.