ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Top Posters(30 Days)
Potseal 11
Recent Posts
600 KW 120/208 3 Phase Y protection
by Yooperup. 07/20/17 09:56 AM
Green House wiring
by ghost307. 07/20/17 09:10 AM
1913 American Electrician's Handbook
by Potseal. 07/20/17 08:42 AM
Permit Snafus...AHJs and Contractors Jump in
by HotLine1. 07/18/17 08:06 PM
New in the Gallery:
SE cable question
Popular Topics(Views)
239,164 Are you busy
174,544 Re: Forum
166,984 Need opinion
Who's Online Now
1 registered members (Yooperup), 57 guests, and 9 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate This Thread
#78426 - 09/22/01 11:13 PM Re: Working Clearance for HVAC Equip  
Bill Addiss  Offline
Member
Joined: Oct 2000
Posts: 3,878
NY, USA
From the 'Mailbag'
Quote
I have installed a 7 1/2 ton split system air conditioning unit in an electrical/communication room. It is 460 V 3 phase. According to the UMC I need to have a 30" X 30" clear access for where the power is tied into the unit and for controls. I have an inspector who is saying that I must go by the NEC and have 30" X 42" clear access, due to the voltage. Can you help me out.
Thanks


2017 / 2014 NEC & Related Books and Study Guides

#78427 - 09/23/01 10:53 AM Re: Re: Working Clearance for HVAC Equip  
electure  Offline


Member
Joined: Dec 2000
Posts: 4,260
Fullerton, CA USA
Your inspector is correct if you have a grounded surface on the opposite side of the workspace.
NEC 110-16 deals with working clearances.
Table 110-16(a) gives the working clearances as they apply do different situations.
At 151-600V to ground, the clearances are:
1)No live or grounded parts on other side=3'
2)Grounded parts on the other side=3-1/2'
3)Live parts on both sides=4'

In any case, the 30" in the UMC is not sufficient by NEC, as the requirement at 0-150V is 3' in any of the conditions mentioned above.



Member Spotlight
watersparkfalls
watersparkfalls
Washington...Not DC
Posts: 216
Joined: March 2005
Show All Member Profiles 
Featured:

2017 NEC and Related
2017 NEC
Now Available!

Shout Box
Powered by UBB.threads™ PHP Forum Software 7.6.0
Page Time: 0.008s Queries: 14 (0.002s) Memory: 0.7444 MB (Peak: 0.8603 MB) Zlib enabled. Server Time: 2017-07-20 14:27:53 UTC