The Electrical Contractor Network

ECN Electrical Forum
Discussion Forums for Electricians, Inspectors and Related Professionals

Books, Tools and Test Equipment for Electrical and Construction Trades

Register Now!

Register Now!

We want your input!

Featured:
   

2017 NEC and Related
2017 NEC
Now Available!

   
Recent Posts
Sprinklered equipment 26-008
by bigpapa
12/02/16 04:24 PM
On Delay Relay with Auto Reset
by Potseal
12/01/16 09:59 AM
Wow, that was close!
by jraef
11/28/16 07:06 PM
Earthquake in New Zeeland
by RODALCO
11/27/16 11:25 PM
Calling all Non-US members!! (Non-US only)
by Tjia1981
11/27/16 06:33 AM
New in the Gallery:
12.5A through 0.75mm˛ flex (just out of curiosity)
Shout Box

Top Posters (30 Days)
gfretwell 13
HotLine1 9
Texas_Ranger 8
sparkyinak 7
Trumpy 6
Who's Online
1 registered (LongRunner), 221 Guests and 4 Spiders online.
Key: Admin, Global Mod, Mod
Topic Options
Rate This Topic
#183339 - 01/05/09 10:26 AM 208v fan coil motors
ucan Offline
New Member

Registered: 01/05/09
Posts: 1
Loc: chicago
I'd appreciate some input. I have several carrier fan coils used in commercial applications. They were installed in 1992. They all have single phase 208 volt 1 hp motors and toggle type 2 pole double disconnect switches. However, the control is provided with a pneumatic/electric switch (the hvac controls all use air) which only switches one leg of the supply to the motor. This seems unsafe as the other leg stays energized.
The original drawings called for 120v motors with this control setup. somewhere along the line the fan coils ended up being 208v.
Would appreciate any comments.
thanks

Top
2014 / 2011 NEC & Related Books and Study Guides
#183341 - 01/05/09 12:25 PM Re: 208v fan coil motors [Re: ucan]
gfretwell Offline

Member

Registered: 07/20/04
Posts: 9045
Loc: Estero,Fl,usa
As long as you have a real disconnect it is OK to switch one leg in a "controller"
Quote:
430.84 Need Not Open All Conductors.
The controller shall not be required to open all conductors to the motor.
Exception: Where the controller serves also as a disconnecting means, it shall open all ungrounded conductors to the motor as provided in 430.111.
_________________________
Greg Fretwell

Top



ECN Electrical Forums - sponsored by Electrical Contractor Network - Electrical and Code Related Discussion for Electrical Contractors, Electricians, Inspectors, Instructors, Engineers and other related Professionals