Feeder or branch circuit tap help

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cppoly

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For fire pumps, need a little help understanding the terminology. Coming From a fused service disconnect in the cellar of let’s say 400A/350A/3P this feeder goes to pull box on the roof. The pull box then feeds a jockey pump controller and also feeds a fire pump controller.

My first question is, is the fire pump feeder on the load side of the disconnect in the cellar actually considered a fire pump branch circuit since there’s no additional OCPD after this fused disconnect in the cellar?

I’m trying to follow the tap rules for sizing jockey pump controller conductors from the pull box on the roof. But the terminology is throwing me off since the only tap rules I know of are for feeder taps (10’ tap rule and 25’ tap rule based on the feeder OCPD), but if this is a branch circuit tap, I don’t see tap rules for this.
 
If you ask me I would say you were tapping a 350 amp feeder.

JAP>
 
Although I'd be wrong there's just something about calling a circuit of that size a branch circuit that just doesn't seem right to me. :)

JAP>
 
I'm attaching a quick sketch for reference. I think I answered my own question if the jockey pump control panel comes with OCPD then it's a feeder tap. If not, I'm not sure how to size jockey pump conductors.
 

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jap said:
Although I'd be wrong there's just something about calling a circuit of that size a branch circuit that just doesn't seem right to me. :)

JAP>
Click to expand...
if you have an individual load of 1000 amps or even multiple outlet circuit (though that isn't too likely with high amp loads) the circuit between the final overcurrent device and the load is still within the definition of a branch circuit.
 
cppoly said:
For fire pumps, need a little help understanding the terminology. Coming From a fused service disconnect in the cellar of let’s say 400A/350A/3P this feeder goes to pull box on the roof. The pull box then feeds a jockey pump controller and also feeds a fire pump controller.

My first question is, is the fire pump feeder on the load side of the disconnect in the cellar actually considered a fire pump branch circuit since there’s no additional OCPD after this fused disconnect in the cellar?

I’m trying to follow the tap rules for sizing jockey pump controller conductors from the pull box on the roof. But the terminology is throwing me off since the only tap rules I know of are for feeder taps (10’ tap rule and 25’ tap rule based on the feeder OCPD), but if this is a branch circuit tap, I don’t see tap rules for this.
Click to expand...
Is this fused disconnect the service disconnect for other building loads or is it only for the fire pump? Fire pump service disconnect is not supposed to be located with other building disconnect means so that it doesn't get inadvertently shut off when killing building power during fire situations. It can be tapped to line side of the regular building disconnect however. Any overcurrent devices especially if not part of listed fire pump controller need to be able to allow the fire pump to run at locked rotor current indefinitely.
 
kwired said:
if you have an individual load of 1000 amps or even multiple outlet circuit (though that isn't too likely with high amp loads) the circuit between the final overcurrent device and the load is still within the definition of a branch circuit.
Click to expand...

I know,,,, it just sounds cheesy.

Regardless of definition, I'd rather tell my buddies I worked all day installing a 400 amp feeder instead of telling them I worked all day installing a 400 amp branch circuit.

It just sounds tougher.

JAP>
 
jap said:
I know,,,, it just sounds cheesy.

Regardless of definition, I'd rather tell my buddies I worked all day installing a 400 amp feeder instead of telling them I worked all day installing a 400 amp branch circuit.

It just sounds tougher.

JAP>
Click to expand...
The "pulling of 400 amp conductors" is what sounds harder in either case.;)
 
jap said:
Regardless of definition, I'd rather tell my buddies I worked all day installing a 400 amp feeder instead of telling them I worked all day installing a 400 amp branch circuit.

It just sounds tougher.
Click to expand...
Maybe, maybe not. Saying you pulled a 400a feeder sounds mundane.

Pulling a 400a branch circuit is something you don't hear very often.
biggrin.gif
 
cppoly said:
For fire pumps, need a little help understanding the terminology. Coming From a fused service disconnect in the cellar of let’s say 400A/350A/3P this feeder goes to pull box on the roof. The pull box then feeds a jockey pump controller and also feeds a fire pump controller.

My first question is, is the fire pump feeder on the load side of the disconnect in the cellar actually considered a fire pump branch circuit since there’s no additional OCPD after this fused disconnect in the cellar?

I’m trying to follow the tap rules for sizing jockey pump controller conductors from the pull box on the roof. But the terminology is throwing me off since the only tap rules I know of are for feeder taps (10’ tap rule and 25’ tap rule based on the feeder OCPD), but if this is a branch circuit tap, I don’t see tap rules for this.
Click to expand...

Your pump controllers don't have integral overcurrent devices? If so there is your branch circuit devices and your line from the cellar is a feeder circuit.
 
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