Fire Pump and Jockey Pump Circuit with Taps?

[don_resqcapt19]

This scenario is really really odd because 240.21 and 430.28 all are about feeder taps, but we are not tapping at any feeders. We are tapping lugs on the load side of a service fuse. So tap rule does this apply to?

The following was a proposal for the 2011 code. Note that feeders begin at the load side of the service overcurrent protective device.

10-45 Log #4825 NEC-P10 Final Action: Reject
(240.21(B))
_______________________________________________________________
Submitter: Don Ganiere, Ottawa, IL
Recommendation: Add text to read as follows:
(B) Feeder Taps. Conductors shall be permitted to be tapped, without
overcurrent protection at the tap, to a feeder as specified in 240.21(B)(1)
through (B)(5). Feeder taps shall be permitted to originate at the load terminal
of an overcurrent protective device. The provisions of 240.4(B) shall not be
permitted for tap conductors.
Substantiation: This type of installation is permitted in many areas, but the
code does not specifically permit it. The additional wording will make it clear
that this is a code compliant installation. As long as all of the conditions of this
section are complied with the point of origination of the tap conductor does not
create any additional hazard.
Panel Meeting Action: Reject
Panel Statement: The proposed language is not necessary as the present
language permits such installation where appropriate.
Number Eligible to Vote: 12
Ballot Results: Affirmative: 12

In the 2020 the code language was changed to try and clarify the issue with the underlined text below being added to 240.21(B), but I think the rejected language in my proposal above was better

(B) Feeder Taps.
Conductors shall be permitted to be tapped, without overcurrent protection at the tap, to a feeder as specified in 240.21(B)(1) through (B)(5). The tap shall be permitted at any point on the load side of the feeder overcurrent protective device. Section 240.4(B) shall not be permitted for tap conductors.

 

[Tainted]

The following was a proposal for the 2011 code. Note that feeders begin at the load side of the service overcurrent protective device.


In the 2020 the code language was changed to try and clarify the issue with the underlined text below being added to 240.21(B), but I think the rejected language in my proposal above was better

Their language is weird see in the bolded text:

The tap shall be permitted at any point on the load side of the feeder overcurrent protective device.

The way I read it is that a service overcurrent protective device cannot be tapped, only a feeder overcurrent protective device can. I think their way of writing it is misleading. Obviously they don't mean it that way.

It should be something like this:

The tap shall be permitted at any point on the load side of the overcurrent protective device protecting the associated feeder(s).

But yes I agree your clarification is better than theirs

 

[don_resqcapt19]

The service OCPD is really a feeder OCPD in all cases. It can only provide overload protection for the service conductors, but provides overcurrent protection to the conductors on the load side.

I have always had a problem with the use of the term "service overcurrent protection" as no device can provide overcurrent protection as defined in Article 100, where the device is installed at the load end of the conductors as is the case with the service "overcurrent" device.

 

[Tainted]

The service OCPD is really a feeder OCPD in all cases. It can only provide overload protection for the service conductors, but provides overcurrent protection to the conductors on the load side.

I have always had a problem with the use of the term "service overcurrent protection" as no device can provide overcurrent protection as defined in Article 100, where the device is installed at the load end of the conductors as is the case with the service "overcurrent" device.

Right, there is no definition for a "service overcurrent protection" I guess I unknowingly used it as a slang term.

At this point I'm not quite sure which one of the tap rules apply to my situation, 240.21 or 430.28?

 

[don_resqcapt19]

Right, there is no definition for a "service overcurrent protection" I guess I unknowingly used it as a slang term.

At this point I'm not quite sure which one of the tap rules apply to my situation, 240.21 or 430.28?

The title of Part VII of Article 230 is "Service Equipment Overcurrent Protection", so not really slang. That is what the code calls it, even though, there is no way that it can actually provide overcurrent protection for the service conductors.

I think the only real difference between the two rules would be that the rule in 430 would permit the tap conductor to terminate on an OCPD sized in accordance with 430.52, and the rule in 240 would require the OCPD to be equal to or less than the ampacity of the feeder tap conductor.
In this case the size of the feeder conductor will be much larger than what is required for the circuit, so it would make any difference. You will run a conductor with an ampacity of at least 133 amps, and no more than 25' in length between the load size of the 400 amp fuse to the line side of the next OCPD.

 

[Tainted]

The title of Part VII of Article 230 is "Service Equipment Overcurrent Protection", so not really slang. That is what the code calls it, even though, there is no way that it can actually provide overcurrent protection for the service conductors.

I think the only real difference between the two rules would be that the rule in 430 would permit the tap conductor to terminate on an OCPD sized in accordance with 430.52, and the rule in 240 would require the OCPD to be equal to or less than the ampacity of the feeder tap conductor.
In this case the size of the feeder conductor will be much larger than what is required for the circuit, so it would make any difference. You will run a conductor with an ampacity of at least 133 amps, and no more than 25' in length between the load size of the 400 amp fuse to the line side of the next OCPD.

This means I would need 1/0 wires to the jockey pump disconnect. The only problem is that I am not sure yet if the lugs inside the 30A switch would be able to take 1/0.

My idea:
1. Install a splice box near the 30A switch.
2. Run 1/0 wires from the 1st overcurrent device into the splice box.
3. Tap the 1/0 wires inside the splice box using #10 wires for the jockey pump disconnect switch.

The only issue with my idea is that I think the wires between the 1st overcurrent device and splice box is considered a tap conductor and therefore I cannot tap a tap inside the splice box. (Correct me if I'm wrong)

 

[don_resqcapt19]

This means I would need 1/0 wires to the jockey pump disconnect. The only problem is that I am not sure yet if the lugs inside the 30A switch would be able to take 1/0.

My idea:
1. Install a splice box near the 30A switch.
2. Run 1/0 wires from the 1st overcurrent device into the splice box.
3. Tap the 1/0 wires inside the splice box using #10 wires for the jockey pump disconnect switch.

The only issue with my idea is that I think the wires between the 1st overcurrent device and splice box is considered a tap conductor and therefore I cannot tap a tap inside the splice box. (Correct me if I'm wrong)

You are not wrong. I think you will have to go with a 100 amp, or even larger, fusible switch, and use fuse reducers to adapt down to the correct fuse size.

 

[d0nut]

If the jockey pump has a separate controller like was illustrated in the first sketch, why not just feed it off of the building's normal power system and skip all of this mess with taps, large disconnects, and fuse reducers? Nothing in Article 695 applies to the jockey pump.

 

[gadfly56]

If the jockey pump has a separate controller like was illustrated in the first sketch, why not just feed it off of the building's normal power system and skip all of this mess with taps, large disconnects, and fuse reducers? Nothing in Article 695 applies to the jockey pump.

Notwithstanding 695.1(B)(2), there is 695.3(A), 695.3(A)(1), 695.5(B), 695.5(C)(1), 695.6(B)(1), and 695.6(I)(6).

 

[d0nut]

Notwithstanding 695.1(B)(2), there is 695.3(A), 695.3(A)(1), 695.5(B), 695.5(C)(1), 695.6(B)(1), and 695.6(I)(6).

I should have been more careful with my language.

What I was getting at is that you are not required to feed the jockey pump from the fire pump service, which is what is causing the OP all of the issues in this case. In lieu of hammering this square peg into a round hole, why not put the square peg in the square hole by using the building's normal power service and equipment rather than the fire pump's service?

You are certainly allowed to feed the jockey pump from the fire pump's service and follow all of the rules in the references noted, but why go through that headache in this particular instance?

 

[Tainted]

I should have been more careful with my language.

What I was getting at is that you are not required to feed the jockey pump from the fire pump service, which is what is causing the OP all of the issues in this case. In lieu of hammering this square peg into a round hole, why not put the square peg in the square hole by using the building's normal power service and equipment rather than the fire pump's service?

You are certainly allowed to feed the jockey pump from the fire pump's service and follow all of the rules in the references noted, but why go through that headache in this particular instance?

I agree, and I have told the electrician this and he kept arguing with me saying that the jockey pump should be treated like a fire pump as per NYC electrical code. Of course he misinterpreted the code and didn't listen to me, and now I'm seeing all these issues and he didn't follow the tap rule when I clearly said to do so. All this stuff is already installed so now I'm verifying everything to make sure it's per code.

 

[Tainted]

You are not wrong. I think you will have to go with a 100 amp, or even larger, fusible switch, and use fuse reducers to adapt down to the correct fuse size.

I have another idea... but I am not sure how to size the wire for it.

Instead of having taps at the fuse, why don't I just bring a 3-phase conductor into a splice box next to both the fire pump and jockey pump disconnect switches and tap from that? See edited picture.

Do I size the conductors between the 400A fuse and splice box based on the 400A fuse or should I just size it based on 125% of the total full load currents of the jockey pump and fire pump?

What about the conductors after the splice box?

The splice box will be less than 10 feet from the two jockey pump and fire pump disconnect switches

 

[gadfly56]

I agree, and I have told the electrician this and he kept arguing with me saying that the jockey pump should be treated like a fire pump as per NYC electrical code. Of course he misinterpreted the code and didn't listen to me, and now I'm seeing all these issues and he didn't follow the tap rule when I clearly said to do so. All this stuff is already installed so now I'm verifying everything to make sure it's per code.

You and d0nut are both correct; it may be treated as the fire pump but it doesn't have to be. Specifications might require it, but that's another story.

 

[Tainted]

You and d0nut are both correct; it may be treated as the fire pump but it doesn't have to be. Specifications might require it, but that's another story.

I figured out what I must do. I read something in the official NYC code interpretation committee website that told you step by step how to size the wires and overcurrent protection if the fire pump and jockey pump are on the same circuit. The electrician will have to re-do some of the circuits. Also found somewhere in the NYC code interpretation committee also tells you a jockey pump is not considered a emergency circuit. So now I have something to back up my claims if the electrician disagrees with me.

 

[l3city]

Service conductors can be Spliced or Tapped per NEC 230.33..No need for disconnects and all this stuff...Also, the jockey pump can be powered from any normal panel...the J-pump is not required to be tied together with the Fire pump. In fact NEC 695 doesn't want anything to do with Jockey pumps...keep it simple and safe at the same time...no need for all these equipment....