Rtu integral disconnect

[hhsting]

If RTU has integral fused disconnect and fed from panelboard B breaker1 then are conductors between breaker1 and fused disconnect feeders or branch circuit? I saw the definition of feeder and branch circuit NEC 2017 Article 100 but was not sure.

 

[hhsting]

If RTU has integral fused disconnect and fed from panelboard B breaker1 then are conductors between breaker1 and fused disconnect feeders or branch circuit? I saw the definition of feeder and branch circuit NEC 2017 Article 100 but was not sure.

Anyone?

 

[infinity]

Is the integral OCPD's supplementary protection?

 

[hhsting]

Is the integral OCPD's supplementary protection?

Its manufacturer provided fused disconnect. The RTU fused disconnect is fed from breaker in panelboard located in first floor. The fused disconnect is at the RTU on the roof

 

[infinity]

By definition it's a feeder but I don't see anything that can stop you from calling it supplementary protection which makes it a branch circuit. The code language on supplementary protection is pretty lame.

 

[wwhitney]

If RTU has integral fused disconnect and fed from panelboard B breaker1 then are conductors between breaker1 and fused disconnect feeders or branch circuit?

What practical difference does it make? I.e is there a code section that result in a difference in requirements for the two possibilities?

Cheers, Wayne

 

[augie47]

I've seen "experts" disagree on this often.
I agree with wwhitney... it really makes no difference if you call it since the requirements would be the same regardless.
See 430.23

 

[hhsting]

What practical difference does it make? I.e is there a code section that result in a difference in requirements for the two possibilities?

Cheers, Wayne

Well it would make a difference if I had heater with integral fused disconnect in tenant space is not guest suites or not guest room and it is fed from panel breaker outside of tenant space. I would need to know it the conductors between outside panel breaker and the fused disconnect are feeder or branch circuits for enforcement of NEC 2017 Article 240.24(B).

If the conductors are feeders and that integral fused disconnect branch circuits overcurrent protection device then they are ready access to it tenant. If not then they are not.

What do you think?

 

[wwhitney]

What do you think?

For 240.24(B), I don't see how the phrase "all overcurrent devices protecting the conductors supplying that occupancy" differentiates between feeders and branch circuits.

Cheers, Wayne

 

[hhsting]

For 240.24(B), I don't see how the phrase "all overcurrent devices protecting the conductors supplying that occupancy" differentiates between feeders and branch circuits.

Cheers, Wayne

It differentiates. 240.24(B) has exceptions. So if I have multi occupancy building and my tenant in that building is not guest rooms or guest suites then my feeder overcurrent protection devices can be accessible to management personnel only but my branch circuit overcurrent protection device mist be accessible to its occupants.

Now i need to know in that case if I have feeder or branch circuit

 

[wwhitney]

It differentiates.

240.21(B)(1) only applies to "feeder overcurrent devices supplying more than one occupancy." So if this indeterminate branch circuit/feeder is only supplying one occupancy, 240.21(B)(1) provides no relief to making the upstream overcurrent device accessible, even it is determined to be a feeder.

But to answer the question in the OP, if the integral disconnect has a UL 489 listed circuit breaker or UL 248 listed fuse, I would say that is the branch circuit overcurrent protection, so the supply is a feeder. While if it is only a switch or a recognized component rather than a listed device, then the supply is a branch circuit.

Cheers, Wayne