Fire water pump controller - vs- combination starter

[mwrichard]

Is there a difference? If so what are the major differences. I'm supposing one would be the absence of overloads.

Reading article 695 and researching various sites on the net and I keep reading about "pump controllers". Is this a generic term for this application or would one use a combination starter.

More specifically, I have two existing motors/pumps. A 50HP will serve as the primary and run 24/7. On low pressure the second, a 100HP, will start. Upon further pressure drop a diesel back-up will start. Will conventional combination starters be suitable for this application or are there special devices for this application?


Any input welcome.

 

[kiloamp7]

Re: Fire water pump controller - vs- combination starter

No question, there are "special" devices that are listed & that are used as fire pump controllers. A regular combination starter will not get it, even if you modified the OCP, etc.
They have many features that are required by various codes & regulatory agencies. Heck, they are even painted red.

 

[charlie]

Re: Fire water pump controller - vs- combination starter

A listed fire pump controller will open under locked rotor conditions after about 20 seconds. There are other listing requirements that are different as well. Basically, if it is a fire pump, it takes a fire pump controller. If you want to save some bucks, get a fire pump controller that is SUSE rated and use it for service equipment.

 

[tom baker]

Re: Fire water pump controller - vs- combination starter

Will conventional combination starters be suitable for this application
No
or are there special devices for this application?
Yes
They are painted red, and are listed for fire pump service, IE expensive.
They have dry contacts to allow monitoring by a fire alarm type panel, and the requirements are laid out in NPFA 20. The NEC covers the wiring to the fire pump, NFPA 20 has all the rules, you'll need a copy.
One special feature is a manual override to close the contactor and hold it in. The fire pump or motor is sacrificed for the fire, hence there are no overloads.

 

[steve66]

Re: Fire water pump controller - vs- combination starter

I'm confused. Are these pumps used for a sprinkler system? If so, why would one run 24/7? Usually the fire pump starts when flow is detected.

Steve

 

[charlie]

Re: Fire water pump controller - vs- combination starter

Steve, there are times when the water pressure is not sufficient to fight a fire. A fire pump may be used to feed sprinkler systems or standpipes or both. When a fire pump is running, it will literally suck water out of the pipes that feed a facility to keep the pressure up.

 

[tom baker]

Re: Fire water pump controller - vs- combination starter

Often a fire pump system will have a small pressure maintainer pump of 10 hp and a larger fire pump of perhaps 50 hp.
We took over a fire pump system several years ago, its a lot of very specific installation and weekly testing.

 

[mwrichard]

Re: Fire water pump controller - vs- combination starter

Steve66, There is a 50HP that maintains the charge/pressure in the lines while the firewater is not in use. (not for spinklers but for fire monitors around a small process unit) When pressure drops to a predetermined setpoint, the larger pump kicks in and if it continues to drop, a back-up diesel driven pump starts...that's the basic control scheme; it's a little more involved but that's the basic operation form what I'm learning about it.

Thanks for the info gents!

[ April 13, 2005, 08:53 AM: Message edited by: mwrichard ]

 

[steve66]

Re: Fire water pump controller - vs- combination starter

OK, thanks for clearing that up. I understand make-up pumps and fire pumps, but I just thought a 50HP pump to maintain pressure with no flow seemed huge.

Maybe this is your application:

Worlds tallest building

Steve