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

>> Home   >> Electrical-Photos   >> Classifieds   >> Subscribe to Newsletter   >> Store  
 

Featured:

 Electrical
 Clearance

 *
 Tools
 *

 Books

 *

 Test Equipment

 

Recent Gallery Topics:
What in Tarnation?
What in Tarnation?
by timmp, September 10
Plumber meets Electrician
Plumber meets Electrician
by timmp, September 10
Who's Online Now
0 members (), 309 guests, and 10 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
#183339 01/05/09 02:26 PM
Joined: Jan 2009
Posts: 1
U
ucan Offline OP
New Member
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

Work Gear for Electricians and the Trades

Workgear for Electricians

Joined: Jul 2004
Posts: 10,048
Likes: 38
G
Member
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

Link Copied to Clipboard
Powered by UBB.threads™ PHP Forum Software 7.7.5