ECN Forum
Posted By: Yoopersup Fire Pumps - 07/02/06 05:58 PM
Fire pump has two sources of power Generator , Normal power. Both run thur a Transfer switch.One Can the Generator feed a Common Panel that feeds other Loads (Feeders)besides the fire pump???? Two can the Normal power come off a Panel that feeds other Normal power Feeders??? Also Transfer switch and all panels to be located in same electrical room. Article 695 Just want other opions Please.
Posted By: Alan Nadon Re: Fire Pumps - 07/03/06 07:42 PM
Definate Maybe. Tending toward No.
695.3 covers power supplies.
In 25 years of inspecting I haven't seen common supply / normal supply for a fire pump but, I have for a booster pump.
Alan--
Posted By: George Little Re: Fire Pumps - 07/03/06 08:53 PM
Ernie- I thought no one was going to give an opinion but alan was brave enough to start the ball rolling.
I just read 695.3 ('02 NEC) and what I get out of it is the key word "reliable" and if this system is "reliable" than there are some options that kick in. They are listed in 695.3. Knowing you you've already read them. If this is a "Required" fire pump and I'm sure it is, than Article 700 would kick in. The transfer switch and associated wiring needs to be installed in such a way to give priority to the fire pump. We are talking about load shedding and capacity as well as the isolation of wiring. I don't have NFPA 20 but I'm sure some Engineer on this BB will join in and help us. Kinda a "straddle the fence answer but then, I'm not a fire pump expert by any means. See Ya in September as well as Alan Nadon
Posted By: Yoopersup Re: Fire Pumps - 07/03/06 09:42 PM
Casino on Native American land.But my concern is if Fault on one of the other feeds drops out main on Generator or Normal power Panel. There goes your Fire Pump. To me not really clearly defined,They also designed it without load sheeding.I;m reviewing prints for them but can only give my opinion.
Posted By: SteveFehr Re: Fire Pumps - 07/04/06 01:47 AM
Do your panels have any PLC logic to do intelligent load shedding/switching, or is it just the ATS? Sounds like no [Linked Image]

One thing you could do is manually switch all the loads off BUT the firepump and emergency lighting on the emergency switchboard, such that you can use the generator to power other loads, but only if manually switched. Kirk-key can enforce this, if you're worried about them "cheating" and only allow them to unlock the breakers when the ATS has switched to generators.

[This message has been edited by SteveFehr (edited 07-03-2006).]
Posted By: Steve T Re: Fire Pumps - 07/06/06 03:47 AM
Just happen to have the same issue.

In my understanding the normal power has to come from a separate service or a tap located ahead of and not within the same cabinet, enclosure, or vertical switchboard section as the service disconnecting means.--695.3(A)(1).

The generator power shall be of sufficient capacity to allow normal starting and running of the motors driving the fire pump while supplying all other simultaneous loads.--695.3(B)(1)

Also-- A tap ahead of the on-site generator disconnecting means shall not be required.-- 695.3(B)(1)

So--One--Yes. Two--No.

As far as the transfer switch in the electrical room 695.6(A) Exception allows the conductors to be in there without being fire rated. What can't happen is running the conductors overhead through the building unless encased in concrete or be a listed electrical circuit protective system, which means you can use rated conductors in rigid. Someone does make such a thing and when the contractor forgets to bury his conduit, it becomes the only option in many cases.

Now, 695.6(B) list number 2 and it's exception are directly contradictory, so your guess is as good as mine in that situation.
Posted By: frenchelectrican Re: Fire Pumps - 07/06/06 05:18 AM
the other thing about fire pump[s] i did not see anyone mention about setting the ocpd for LCA [ locked rotor amps or current ] i think it was stated in the NEC and NFPA [ the NFPA i am not sure where it did fall in but i do know it did mention LCA ]

so you may have to check the transfer switch to handle LCA.

some case you may have to use the " oversized " ats or mts [ manual transfer switch ]

so just check it out ahead of time

Merci , Marc
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