Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Electrical

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 01-07-2011, 09:28 PM   #1
Member
 
analogmusicman's Avatar
 
Join Date: Feb 2008
Location: colorado springs
Posts: 591
Share |
Default

lights "strobe"


funny thing about the lights in this bathroom I'm doing over: they flicker at the line frequency (I guess) so they produce a "strobing" effect. never noticed this before,maybe it's a recent thing. gives me a durned headache as I try to remove the wallpaper. haven't checked if the outlets do it too. could the GFCI be doing this. didn't think lights had to be on a GFCI.
any ideas?

tnx,

analogmusicman is offline   Reply With Quote
Old 01-07-2011, 09:42 PM   #2
Mad Scientist
 
Join Date: Dec 2009
Location: Minnesota
Posts: 761
Default

lights "strobe"


What kind of lights? Florescent lights can do that if the bulbs or ballast are going bad. Incandescent shouldn't, though, unless there's a loose connection.

McSteve is online now   Reply With Quote
Old 01-07-2011, 09:59 PM   #3
Member
 
analogmusicman's Avatar
 
Join Date: Feb 2008
Location: colorado springs
Posts: 591
Default

lights "strobe"


yeah, these are "incandesent" lights,strange huh?
(a loose connection wouldn't cause this kind of regular flicker)
I was thinking of some sort of inductive load on the light circuit and indeed it DID look like the flickering coincided with the furnace blower coming on, but that didn't seem to work out. (the furnace is only a couple months old) still considering that though!

tnx,
analogmusicman is offline   Reply With Quote
Old 01-07-2011, 10:04 PM   #4
nap
You talking to me?
 
nap's Avatar
 
Join Date: Dec 2007
Location: sw mi
Posts: 5,407
Default

lights "strobe"


Quote:
they flicker at the line frequency
you can see 60 hz?

Is there a dimmer on them?
nap is offline   Reply With Quote
Old 01-08-2011, 08:24 AM   #5
Member
 
Join Date: Nov 2007
Location: Nashua, NH, USA
Posts: 6,862
Default

lights "strobe"


Light Emitting Diode (LED) fixtures may flicker at 60 Hz. But the tiny individual lamps inside may be wired to flash alternately giving a 120 Hz effect that hardly anybody notices.

Most fluorescents flicker at 120 Hz. Incancescents also get 120 pulses of power each second as the positive and negative portions of the 60 Hz AC come into play except that some dimmers alter the power to deliver 60 pulses per second that may be noticed with incandescents also. There may also be a visible difference between a short angular pulse every 1/60 second compared with round pulses (from sine waves) occupying most of every 1/120'th second time slot.

Regular LED's light only on the positive pulses or only on the negative pulses depending on which way the little lamps are wired in. They do make "tandem" LED lamps with two glowing elements inside the usual grain of wheat sized bulb, sometimes red for the positive pulses and green for the negative pulses (and yellow when both are energized) and used for color effects.

Some people see 60 Hz flicker. This has been annoying with older computer screens and many computers offer 70 Hz and sometimes faster "refresh" for the screen. On extremely old computer screens and TV sets, every row of pixels may flicker at (approx.) 30 Hz. with odd rows and even rows offset halfway, by 1/60'th second to give the overall picture although not necessarily the crosses of T's and dots of I's a refresh of at least 60 Hz.

Once in awhile the filament of an incandescent lamp vibrates, giving a flickering effect as shadows cast by the light move slightly.
__________________
Stop wasting time re-adjusting the pattern. Have several lawn sprinklers, one for each pattern.

Last edited by AllanJ; 01-08-2011 at 09:01 AM.
AllanJ is offline   Reply With Quote
Old 01-08-2011, 09:47 PM   #6
nap
You talking to me?
 
nap's Avatar
 
Join Date: Dec 2007
Location: sw mi
Posts: 5,407
Default

lights "strobe"


Quote:
Originally Posted by AllanJ View Post

Once in awhile the filament of an incandescent lamp vibrates, giving a flickering effect as shadows cast by the light move slightly.
that is kind of what I was after. I have seen filaments vibrate and even "sing" due to being on a dimmer.
nap is offline   Reply With Quote
Old 01-09-2011, 08:25 PM   #7
Member
 
analogmusicman's Avatar
 
Join Date: Feb 2008
Location: colorado springs
Posts: 591
Default

lights "strobe"


Quote:
Originally Posted by nap View Post
you can see 60 hz?

Is there a dimmer on them?

any electrician "worth his salt" can see a 60 cy. flicker,just as most can recognize a 60 cy. "hum". you ARE "worth your salt" aren't you nap?

tnx,
analogmusicman is offline   Reply With Quote
Old 01-09-2011, 09:57 PM   #8
Member
 
Join Date: Nov 2007
Location: Nashua, NH, USA
Posts: 6,862
Default

lights "strobe"


Not everyone can see a flicker as fast as 60 Hz.

But a person is more likely to notice a flicker when seeing the light out of the corner of the eye as opposed to looking directly at it.

__________________
Stop wasting time re-adjusting the pattern. Have several lawn sprinklers, one for each pattern.
AllanJ is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Finding underground electric wire for driveway lights. mitch21131 Electrical 25 09-24-2012 08:52 AM
Use factory fog light switch for aftermarket lights? downunder Automotive Repairs 6 07-10-2010 11:45 AM
Wiring up an outside set of motion sensing lights airdaleairdale Electrical 1 06-11-2009 08:35 PM
Changing switch for lights in basement, confused on current wiring. RyanD Electrical 2 05-14-2009 08:37 PM
Adding can lights to an existing circuit TexasEd Electrical 1 06-17-2008 07:23 PM




Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.