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. 07/24/17 12:20 PM
1913 American Electrician's Handbook
by gfretwell. 07/20/17 01:08 PM
Green House wiring
by ghost307. 07/20/17 09:10 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)
239,354 Are you busy
174,816 Re: Forum
167,201 Need opinion
Who's Online Now
0 registered members (), 59 guests, and 4 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate This Thread
#177857 - 05/13/08 09:47 PM Metal halide light tripping  
schenimann  Offline
Member
Joined: Feb 2008
Posts: 193
Western North Carolina
I went on a service call yesterday. In a store downtown, a lady had a 250 watt metal halide light that would trip off then come back on. The breaker never trips, only the light. It would do this once, maybe twice a day, sometimes not at all. It is a fairly new fixture, isn't in a location where it would build up excessive heat and it is a 250w ballast.

The outlet that it is plugged into was originally a 220 outlet converted to a 110. Whoever had worked on it previously had used one of the hots and the ground as a neutral. Our fix was to use the other hot as a neutral and yes, we did go to every jbox we could trace and mark it neutral. Would using the ground as a neutral cause the light to trip? If not, what else?


Work Gear for Electricians and the Trades

#177859 - 05/13/08 10:03 PM Re: Metal halide light tripping [Re: schenimann]  
sparkyinak  Offline
Member
Joined: Jul 2007
Posts: 1,327
Alaska
Bad bulbs. HPS does the same thing


"Live Awesome!" - Kevin Carosa

#177860 - 05/13/08 10:33 PM Re: Metal halide light tripping [Re: sparkyinak]  
twh  Offline
Member
Joined: Mar 2004
Posts: 916
Regina, Sask.
I agree a bad HPS bulb will cycle. I'm not sure about MH bulbs. I thought I saw it last week, but when I suggested a new bulb, the carpenters were all over me. They had already tracked it down to voltage drop when another piece of equipment started. Now, I don't think I've seen an MH bulb do that.


#177861 - 05/13/08 11:26 PM Re: Metal halide light tripping [Re: twh]  
renosteinke  Offline
Cat Servant
Member
Joined: Jan 2005
Posts: 5,316
Blue Collar Country
You probably had a high resistance ground ... this had the effect of lowering the voltage .... not enough volts, bulb would try to re-strike.


#177862 - 05/13/08 11:28 PM Re: Metal halide light tripping [Re: renosteinke]  
schenimann  Offline
Member
Joined: Feb 2008
Posts: 193
Western North Carolina
Should fixing the neutral fix this?



Member Spotlight
sparky66wv
sparky66wv
West Virginia
Posts: 2,236
Joined: November 2000
Show All Member Profiles 
Featured:

2017 Master Electrician Exam Preparation Combos
2017 NEC Electrician
Exam Prep Combos:
Master / Journeyman

 

Shout Box
Powered by UBB.threads™ PHP Forum Software 7.6.0
Page Time: 0.012s Queries: 15 (0.003s) Memory: 0.7683 MB (Peak: 0.9084 MB) Zlib enabled. Server Time: 2017-07-27 00:45:42 UTC