Heat trace high rise on emergency system

[hhsting]

I have high rise building 120 feet high. Bottom three floors above ground are car garage that has wet pipe, dry pipe sprinkler that has heat trace. The heat trace is fed from emergency 50A 277V circuit breaker from 277/480V three phase emergency panelboard fed by generator that has emergency branch.

Would NEC 2017 still require heat trace for fire protection sprinkler pipe to have GFPE or not? Its fed from emergency branch in high rise building.

 

[tom baker]

Did you review the NEC article on heat trace?

 

[hhsting]

Did you review the NEC article on heat trace?

Yes NEC 2017 section 427.22. The high rise is A-3,B,R-2,S-2.

I am wondering if its hidden elsewhere in NEC 2017 since heat trace is on emergency panelboard which is emergency branch of high rise generator

It gets confusing

 

[tom baker]

Why does heat trace have to be on a GFPE circuit?
Did you check the index or firms finder for heat trace?

 

[hhsting]

Why does heat trace have to be on a GFPE circuit?
Did you check the index or firms finder for heat trace?

I don’t follow what you are trying to say really. Are you saying NEC 2017 section 427.22 doesn’t apply to post #1? All I see is blueprint handbook NEC 2017 section 427.22 risk of fire being started is substantially reduced by low level arcing if GFPE is applied.

However if breaker fails then so does heat trace on sprinkler pipe and in high rise buildings could be a risk even though heat trace be monitored supervised from Fire Alarm control panel.

 

[don_resqcapt19]

I am not aware of anything in NFPA 13 that would delete the GFP requirement.

I don't think that the power for the heat trace would be permitted to be supplied from an Article 700 system.

It would also be a bit rare that you could use a 50 amp branch circuit to directly supply the heat trace. Most trace that I have seen does not permit more than a 30 amp OCPD.

Also note that standard heat trace is not permitted for use of fire sprinkler piping. NFPA 13 requires that the heat trace be specifically listed for use on fire suppression piping.

 

[augie47]

Hopefully you have engineered drawings. Do the plans call for GFP protection ?

 

[hhsting]

Hopefully you have engineered drawings. Do the plans call for GFP protection ?

Its weird. The branch circuit breaker to the heat trace doesn’t call GFP. Panel schedule in which the branch circuit breaker resides says panel is MLO but then at bottom has note which says to provide Main Breaker with LSIG for the panel but the note is not referenced in panel schedule items. The panelboard is new.

 

[augie47]

Any details on the heat trace controller ? Does it provide GFP ?

 

[hhsting]

I am not aware of anything in NFPA 13 that would delete the GFP requirement.

I don't think that the power for the heat trace would be permitted to be supplied from an Article 700 system.

It would also be a bit rare that you could use a 50 amp branch circuit to directly supply the heat trace. Most trace that I have seen does not permit more than a 30 amp OCPD.

Also note that standard heat trace is not permitted for use of fire sprinkler piping. NFPA 13 requires that the heat trace be specifically listed for use on fire suppression piping.

I dont see in NEC 2017 article 700 it says power from heat trace not be supplied by emergency branch? You know where you got that

 

[hhsting]

Any details on the heat trace controller ? Does it provide GFP ?

None but got response from engineer that they have spec GFPE be with the heat trace controller. I dont have spec i will just have pit note on plans to have inspector verify in field???

 

[augie47]

None but got response from engineer that they have spec GFPE be with the heat trace controller. I dont have spec i will just have pit note on plans to have inspector verify in field???

Good plan
I would verify with the design engineer about it being on an Art 700 circuit. I agree with don in Post #6 in that the systens I;ve seen were on Art 701 Legally Required, not emergency.

 

[don_resqcapt19]

I dont see in NEC 2017 article 700 it says power from heat trace not be supplied by emergency branch? You know where you got that

The NEC does not specify what can be supplied from an Article 700 emergency system. The NEC only tells you how to wire such a system. The only loads that can be supplied by an Article 700 system are loads that are required by another code to be supplied by an Emergency System. I really doubt that the sprinkler heat trace is so required. It any back of supply is required for that, I would expect it to be an Article 701, Legally Required Standby system. Here again, the NEC only tells you how to wire such a system. The loads that are required to be connected to that system are legally required by some other code or document.