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Posted By: Steve T fire pump OCPD - 10/21/06 12:20 AM
If the fire pump controller enclosure has an OCPD in it, is it subject to article 695?
Posted By: Yoopersup Re: fire pump OCPD - 10/21/06 02:48 AM
Yes
Next Question is ,Is it service rated??
Ect ect
Posted By: Steve T Re: fire pump OCPD - 10/21/06 03:45 AM
I've been told it is not. That the fire pump controller is regulated by NFPA 20.

I have a controller enclosure with a 250 amp OCPD in it. The fire pump is 460 volt, design B, 60 hp, 3 phase, which means the LRA is 435 according to Table 430.151(B).

The engineer of the fire pump controller told me the OCPD is designed to carry 600% of the FLA. He said it would carry this 600% for apx. 8 to 20 seconds.

I am not sure.
Posted By: Yoopersup Re: fire pump OCPD - 10/22/06 12:31 AM
Is it a Listed & Labled unit??
Posted By: Steve T Re: fire pump OCPD - 10/23/06 09:46 PM
I'll have to check, but I think so. Does it have to be a listed and labeled unit? Isn't a unit designed by an engineer acceptable?
Posted By: Steve T Re: fire pump OCPD - 10/23/06 09:56 PM
Here is an excerpt of an email I got in response to my concerns.

The controller in question is our S/N 102490, Peerless #692109, our P/N 705066,
Model MCA-60-46-AHI.
This unit makes use of 250 amp ("F" Frame) molded case circuit breaker (and
isolating switch).
This construction does comply with NFPA-20, UL-218 and FM-1321/1323 fire pump
controller standards.


For a 60 Hp, 460 Vac fire pump motor, the NEC (NFPA-70) value for Full Load Amps
is 77.0 FLA.
The motor will be either a Starting Code "F" or "G" to comply with NFPA-20 Table
9.5.1.1. This allows the motor locked rotor current (LRA) to be up to 600% of
FLA which is 462 amps. The fire pump motor will also be a NEMA Design "B" to comply with NFPA-20 Clause 9.5.1.1.

Although Table 430.151B does apply to NEMA design "B" motors, the LRA value is
only 565% of FLA. Our Fire pump controllers are designed to the higher 600%
(462 Amp) value. The 250 amp rating of the controller Circuit Breaker (and
Isolating Switch) are it's thermal rating. NFPA-20 requires these devices to be
sized at no less than 115% of motor rated FLA. For this motor,
this is 77 x 1.15 = 88.6 amps. Notice that we're using 250 amp devices rather than the 100 amp frame breakers used by our competitors, and as allowed by
code.
Our breaker trip point will be the required 8 to 20 seconds at LRA (462 Amps), also per the codes. Any devices upstream of the controller (fuses, circuit breakers,
switches), however, must be sized at the 600% value or 462 amps, also per code(NFPA-20 and
Article 695 of NFPA-70).
Posted By: Yoopersup Re: fire pump OCPD - 10/24/06 12:35 AM
Put it in . Ul listed and Labeled Service rated Controller.
Posted By: Steve T Re: fire pump OCPD - 10/24/06 10:13 PM
So I do not need to consider the size of the OCPD in the controller per the NEC requirements?

What about thermal rating versus the time curve rating, as stated in the comment? Is this a correct interpretation for 'indefinitely' as used in article 695?
Posted By: electech Re: fire pump OCPD - 10/24/06 10:26 PM
Yoopersup, how do you know it complies with NFPA/NRTL regs? Personal experience with the particular model?

To me such wording as the email used is always a big red flag:

"This construction does comply with NFPA-20, UL-218 and FM-1321/1323 fire pump
controller standards."

It does comply? So says who? "NRTL Listed to standard XYZ" is the type of wording I would find more reassuring. I've seen all sorts of equipment that is "designed to meet" or "complies with the requirements of...", that has never been certified by an OSHA-regulated NRTL or other industry-recognized body. In some cases, as inside your own Listed end-use product, it may OK (but more complicated) to use such unrecognized parts.
Posted By: Yoopersup Re: fire pump OCPD - 10/25/06 01:57 AM
I;ve inspected several units like this. Are you telling me if its a Listed and labled unit you can say no way. Read 695.4 (B)1 A Listed Fire Pump Controller.
695.4 (B) 1 Is for Additional disconnecting means.Read 695.4 COMPLETELY. Not just sections of it.
Posted By: Yoopersup Re: fire pump OCPD - 10/25/06 02:03 AM
But it MUST be a Listed and labled Unit if it is Not then Disconnect must be required to comply with 695.4 (B) 1 & 2 .
Posted By: electech Re: fire pump OCPD - 10/25/06 01:54 PM
I'm not saying no way to a Listed unit. My question is, IS it a Listed unit?.

"This construction does comply with NFPA-20, UL-218 and FM-1321/1323"

I'm always suspicious (even of myself!). "Does comply" could be weasel-wording for "we designed it to meet the requirements of the standard. It was never submitted to an NRTL for certification, but in our opinion it does comply".

I've seen this a gazillion times in telecom. NEBS testing, to meet baby bell's network safety and reliability testing, cost around $100,000 for a complete set of tests on a typical product. Consequently, in marketing literature the words "meets NEBS requirement" and "designed for NEBS" are more common than "NEBS certified". Why spend a hundred grand when you can just use a misleading phrase instead?
Posted By: PCBelarge Re: fire pump OCPD - 10/29/06 02:07 AM
Electech
I agree with what you are saying. The wording "complies with" is not the same as being UL Listed.
Look for the listing and go to the online White Book/Orange Book to see if this unit is in fact UL Listed as suitable.
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