Fire pump

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Shockedby277v

Shockedby277v

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Michigan
Article 695 is making my head spin. Can/do you feed a fire pump from the utility transformer?? I haven't worked with fire pumps enough to know exactly what to do. I do know it needs to be connected before the main disconnect. Any tips would be appreciated.
 
From what I gather from 695.3 (A)(1), is it can't be in the same cabinet, enclosure or verticale switchboard. So The main lugs sound out of the question.
 
Yes, you can run a seperate service to the fire pump but, you don't have to. They are however, overfused to the point that the breaker would never trip. The thinking is that they want the pump to pump the water until the motor burned up rather than tripping breakers and have the building burn down.
If you are going to keep it on the same service and tap ahead of the main breaker the tap can not be made in the service equipment.
You just have to remember to run rigid metal pipe from the controller to the pump (I got popped on that before) The jocky pump doesn't apply (if I remember correctly)
 
Why rigid?? I've seen 2 buildings almost identical to the one I'm doing. Neither had rigid. After getting my prints, I have a ton of questions I would ask or looked into.
 
Shockedby277v said:
Why rigid??
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There are choices other than RMC but EMT is not one of them.

695.6(E) Pump Wiring. All wiring from the controllers to the pump motors shall be in rigid metal conduit, intermediate metal conduit, liquidtight flexible metal conduit, or liquidtight flexible nonmetallic conduit Type LFNC-B, or Type MI cable.
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The fire pump installation I rewired (100 hp electric, 245 hp diesel) have a note on the plans regarding the size of the utility primary fuse, its about 3 times larger than you would normally find.
There is no service disconnect ahead of the electric fire pump.
The service conductors feed directly thru the exterior wall to the fire pump controller.
 
695-6(e) requires rmc or imc then change over to sealtite or carflex for vibration concerns. Type Mi cable is not cost effective. If you ran sealtite all the way from the controller it isn't going to look as good ( workmanship issues). EMT or PVC would be a code violation. The wiring is suppossed to have a 1-hr fire resistance so PVC is definitely out of the question. Almost like a hazardous location. They are just trying to limit the failure of the pump for any reason. Another example is they don't want any overload protection for the pump motor where typically anything over 1 hp would require overload heaters via a starter.
 
willdogyou said:
695-6(e) requires rmc or imc then change over to sealtite or carflex for vibration concerns.
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That is an overstatement of the requirement.

You can run liquid tight flexible nonmetallic conduit the entire distance from the controller to the pump if you want and still meet code.

As the controller is always in the room with the pump (in my experience) the conductors between the controller and the pump do not need a one hour fire rating 695.6(B) exception
 
This is my first job i'm running. There is so much you run into that you don't think about when your not running a job. As I get more experience, I hope it will become easier. The job just broke ground so I have time yet to dig into things. Thnx for the replies.


BTW I would run LFMC. It would take about 4-5' between the motor and the controller.
 
An overstatement of the fire resistance for sure but my opinion is that the allowance of sealtite and liquidtite flexible nonmetallic conduit was intended for the flexible connection to the motor(s) and nothing more.
If you are the electrician worth your weight in salt that has actually been in the field and not just a book worm claiming to KNOWsomething then you would have a safe, pleasing to the eye and within the Code installation. "LFNC all the way to the firepump" is NOT acceptable.
Most CQCM's or Engineers would tell you to tear it out and do it over.
 
willdogyou said:
An overstatement of the fire resistance for sure but my opinion is that the allowance of sealtite and liquidtite flexible nonmetallic conduit was intended for the flexible connection to the motor(s) and nothing more.
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That is a fine opinion but it is not what the NEC states.

Your new here so let me fill you in.

This Forum is a NEC Forum, it is not a 'how I would like to see it done forum.'


If you are the electrician worth your weight in salt that has actually been in the field and not just a book worm claiming to KNOW something then you would have a safe, pleasing to the eye and within the Code installation.
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You really have no idea about me so I will let you know I have been earning a living in the field since I was 17 and I am now 42.

I know more about actual installations than I know about the NEC. I work with the tools almost every day and run jobs from small service work to half a million dollar generator installs.

"LFNC all the way to the firepump" is NOT acceptable.
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To the NEC it is.

Most CQCM's or Engineers would tell you to tear it out and do it over.
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Your right, they might do that depending on the job specifications.

But job specifications, my opinion or your opinion are not NEC code sections.
 
wiildogyou,
An overstatement of the fire resistance for sure but my opinion is that the allowance of sealtite and liquidtite flexible nonmetallic conduit was intended for the flexible connection to the motor(s) and nothing more.
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Can you please cite the code wording that supports your statement?
Don
 
Shockedby277v said:
This is my first job i'm running. There is so much you run into that you don't think about when your not running a job. As I get more experience, I hope it will become easier. The job just broke ground so I have time yet to dig into things. Thnx for the replies.


BTW I would run LFMC. It would take about 4-5' between the motor and the controller.
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I noticed you said LFMC and that would not be acceptable. 695.6(e) says Type LFNC-B. Type "-B" has reinforment in the conduit wall and can be installed in lengths longer than 6 feet in properly supported.

Also, don't confuse the "pump wiring" with the "Power Wiring". The Power Wiring must either be a service conductor or a fire rated circuit conductor with a disconnect/overcurrent sized lock rotor.

Good luck with your first fire pump job. They're not that bad if you have the correct information.

Jim
 
Shockedby277v said:
Why rigid?? I've seen 2 buildings almost identical to the one I'm doing. Neither had rigid. After getting my prints, I have a ton of questions I would ask or looked into.
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The raceway requirement is in regards to after the controller to the fire pump.
 
Thnx for the info Jim. I really appreciate all the help I can get. The fire pump install won't be for a long while but the more information I gather on my own the better. I will still ask my project manager and AHJ on their stance for the fire pump. Atleast when I ask them I will be further ahead thnx to this forum.
 
connectjim said:
I noticed you said LFMC and that would not be acceptable. 695.6(e) says Type LFNC-B. Type "-B" has reinforment in the conduit wall and can be installed in lengths longer than 6 feet in properly supported.
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Jim he did say LFMC

LFMC is permited.

If he said LFNC than he would need LFNC-B but that still has a 6' length limitation.

It also would not surprise me if the 'stocked' versian of LFNC is in fact type B.
 
iwire said:
Jim he did say LFMC

LFMC is permited.

If he said LFNC than he would need LFNC-B but that still has a 6' length limitation.

It also would not surprise me if the 'stocked' versian of LFNC is in fact type B.
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I apoligize and stand corrected that LFMC is acceptable but have to question the 6 foot limit on LFNC. I thought 356.10(5) permitted longer than 6 feet if properly supported in accordance to 356.30.

Also, I noticed they add Type MC cable to 596.6(e) as long as the MC cable has as impervious covering.

Jim C
 
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