Voltage Drop requirements

[dana1028]

just curious - I was reading some comments from an elect-engineer forum and the following statements was made -

"the ASHRAE 90.1 energy code includes maximum permissible voltage drop requirements. ASHRAE 90.1 has been adopted by most US jurisdictions."

This was in response to a previous 'there are no code requirements for voltage drop'.

I am not familiar with ASHRAE 90.1, and I was not aware that 'most' US jurisdictions have adopted this standard [even if they did, who would enforce this?].

 

[dcspector]

American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc....Voltage drop? Maybe they are concerned regarding what EC's are running wire size to their equipment in "hot' attics, length, etc....NOTE:This is an un researched post of mine..BTW...could be their equipment is failing and blaming it on the EC........

 

[ramsy]

I found the most interesting DOE reference on this here ashrae_90_1_2004.pdf

It replaces ANSI/ASHRAE/IESNA Standard 90.1-2001
It proposed to be the reference standard for the 2006 ICC IECC
It is proposed to be the commercial building energy reference in NFPA 5000, NFPA?s family of building codes

Required voltage drop limits
2% on feeders, 3% on branch circuits.

Non DOE versions require a 90% minimum Power Factor for building lighting loads.

 

[MR. S]

voltage drop

voltage drop

The only thing I have seen in the code book about voltage drop are FPN's
215.2(A)FPN No. 2 , ( 3% for feeders, and both feeders and branch circuits
do not exceed 5%), AND 210.19(A) FPN No. 4, ( 3% for branch circuits, and
both feeders and branch circuits do not exceed 5%.) Remember FPN's are
not enforcable. MR. S

 

[charlie b]

The only thing I have seen in the code book about voltage drop are FPN's. . . .

The NEC has minimum requirements to establish a safe configuration. Other codes may be more restrictive. ASHRAE 90.1 is one of them. It does explicitly state, as a mandatory provision, that ?Feeder conductors shall be sized for a maximum voltage drop of 2% at design load.? It also states, ?Branch circuit conductors shall be sized for a maximum voltage drop of 3% at design load.?

However, the fact that ASHRAE 90.1 may have been adopted in a given jurisdiction does not mean that it applies to every installation project that is executed in that jurisdiction. ASHRAE 90.1 is not an electrical code. It is entitled, ?Energy Standard for Buildings Except Low-Rise Residential Buildings.? So it certainly does not apply to most-single family or two-family dwelling units. The question of whether it applies to your next project is a matter for the designer to determine, and the AHJ (i.e., the Building Inspector, not the Electrical Inspector) to enforce.