ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Shout Box
Recent Posts
VDE 0100 to introduce AFCIs
by sparky. 01/20/18 05:09 PM
MRI LED lights dimmer control replacement - wow!
by Potseal. 01/19/18 08:52 PM
Video: Inventor of the GFCI self-testing shocks
by Bill Addiss. 01/17/18 11:11 PM
FPE in Germany
by HotLine1. 01/17/18 07:07 PM
Fujifilm Recalls Power Adapter Wall Plugs
by Admin. 01/16/18 07:04 PM
New in the Gallery:
Housebilding DIY wiring
SE cable question
Who's Online Now
1 registered members (HotLine1), 13 guests, and 13 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
photocell control of fluorescent lt. #46338
12/19/04 12:33 AM
12/19/04 12:33 AM
A
amp-man  Offline OP
Member
Joined: Jun 2001
Posts: 141
Sacto, California US of A
Why is it that the installation instructions for fluorescent light fixtures say not to control the light with a photocell switch?

Cliff

Work Gear for Electricians and the Trades
Re: photocell control of fluorescent lt. #46339
12/19/04 10:28 PM
12/19/04 10:28 PM
Trumpy  Offline

Member
Joined: Jul 2002
Posts: 8,231
SI,New Zealand
Cliff,
I can't see anything wrong with controlling fluorescent lighting with a photocell.
But, I would be careful with selecting the photocell, to make sure that the contacts in the cell can safely make and break the Inductive currents that fluorescent lights generate.

Re: photocell control of fluorescent lt. #46340
12/19/04 11:07 PM
12/19/04 11:07 PM
A
amp-man  Offline OP
Member
Joined: Jun 2001
Posts: 141
Sacto, California US of A
Trunpy,

AHA! Now I understand...

Thanks.

Merry Christmas and a Happy New Year.

Cliff

Re: photocell control of fluorescent lt. #46341
12/19/04 11:20 PM
12/19/04 11:20 PM
H
hbiss  Offline
Member
Joined: Dec 2003
Posts: 886
Hawthorne, NY USA
I believe that there are photo controls out there that do not use a relay but rather a triac in the same way a dimmer does. They only go full on and full off however the waveform can be distorted like that of a dimmer and this is not suitable for fluorescent ballasts.

I think that the ballast manufacturer is just being cautious. Make sure that your photocontrol uses relay contacts and you will be OK.

-Hal

Re: photocell control of fluorescent lt. #46342
12/20/04 05:39 PM
12/20/04 05:39 PM
D
DougW  Offline
Member
Joined: Jun 2003
Posts: 1,143
North Chicago, IL
I 2nd Hal's opinion. I've seen several of the photo units that "flicker" an incandescent in the twilight hours. I can only imagine the havoc that would cause with some of the cheaper imported fixtures...

Re: photocell control of fluorescent lt. #46343
12/20/04 05:58 PM
12/20/04 05:58 PM
C
CTwireman  Offline
Member
Joined: Feb 2002
Posts: 840
Connecticut, USA
I had an $8 photocell go bad that was controlling some fluorescent lights. I hacksawed the thing open, and sure enough it was the relay type.

For some reason, the neutral connection had vaporized, and that's why it went bad.

Peter


Peter
Re: photocell control of fluorescent lt. #46344
12/20/04 06:28 PM
12/20/04 06:28 PM
Trumpy  Offline

Member
Joined: Jul 2002
Posts: 8,231
SI,New Zealand
Personally I'd switch any decent sized Fluorescent installation through a Contactor by cascading the control switch or relay contact with the Contactor coil.
Sure, more expense, but less worries!. [Linked Image]


Featured:

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

 

Member Spotlight
Potseal
Potseal
Saskatchewan
Posts: 259
Joined: February 2013
Show All Member Profiles 
Top Posters(30 Days)
Admin 20
sparky 16
Potseal 15
Popular Topics(Views)
243,571 Are you busy
180,369 Re: Forum
170,845 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.6.1
(Release build 20180101)
Page Time: 0.025s Queries: 15 (0.004s) Memory: 0.9831 MB (Peak: 1.1375 MB) Zlib enabled. Server Time: 2018-01-21 00:46:34 UTC