Timer switch only for incandescents?

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Old 05-29-10, 02:33 PM
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Timer switch only for incandescents?

I have a timer switch that says it can only be used with incandescent bulbs and not fluorescent. Why would this be since I believe it is only a switch? What am I missing? What would happen if I connected it to fluorescent lights?
 
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Old 05-29-10, 03:17 PM
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I hadnt thought about it.. 'coz I still us incans on my exterior lights...on timers.
Might loose life expectancy of the CFL.
.
but this is what I found....

"■Do CFLs work on dimmers?
•Most screw-base CFLs do not work with dimmers designed for use with incandescent lamps. These CFLs will have a label on the lamp and/or the packaging stating "not for use with dimmers. However, certain special screw-base CFLs are designed to work with standard incandescent lamp dimmers. These CFLs will be labeled "dimmable" or similar language on the lamp and/or the packaging. However, due to small differences between different brands of dimmers, not all dimmable CFLs work with all types of incandescent dimmers. Some dimmable CFLs, however, will work with all major brands of incandescent lamp dimmers."
.
There is a difference...
more info ...
Compact fluorescent lamp - Wikipedia, the free encyclopedia
 
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Old 05-29-10, 03:22 PM
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The timer does not have a neutral. Since a timer must always have power for the clock it draws a small amount of power through the light. This can cause weird problems because of the ballast on a fluorescent light.

Assuming you have a neutral at the switch box you can use a timer with neutral for fluorescent lights. Note the presence of a white wire at the switch box does not necessarily mean you have a neutral. If there are only two wires you do not have a neutral. If the only white wire is connected to the switch you do not have a neutral.
 
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Old 05-29-10, 07:32 PM
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Yep, Ray is right. The timer you have won't work with a fluorescent ballast, only with incandescent bulbs. Also, once the incandescent bulb burns out, you'll have to reset the time on the timer as you replace the bulb.
 
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Old 05-30-10, 07:43 AM
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So bottom line guys, what would happen if I tried to use the timer with screw in CFLs?
 
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Old 05-30-10, 08:56 AM
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CFL, FL with ballasts

Most electronic controls such as electronic timers, photo sensors, motion sensors, touch lamps, and remote light controls are designed to work with the simple technology of an incandescent rather than the complex circuitry of a CFL. Electronic controls draw a small amount of electricity to operate that would concurrently run a small amount of electricity through the CFL ballast, placing stress on the electronics. Since CFL ballasts are designed for a specific input voltage and are not designed to handle deviations, imposing them can cause the circuitry to malfunction or not be able to effectively light the lamp or keep the current through the lamp well regulated. The result is that operating CFLs on controls can significantly shorten the lifespan of the product.
 
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Old 05-30-10, 03:22 PM
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Originally Posted by bobfwayne View Post
So bottom line guys, what would happen if I tried to use the timer with screw in CFLs?
I don't think the timer will work.
 
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Old 05-30-10, 03:25 PM
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my guess it will.. come up to norm shortly after powered up. (unlike an reg bulb)
just my $.02
 
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Old 05-31-10, 06:28 AM
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Sometimes a timer designed for incandescent lights will cause CFLs to flicker dimly when they are supposed to be off. This is due to the timer requiring a little bit of power to run the electronics. On an incandescent light, the small power is fed through the filament and no one is the wiser. CFLs use that little bit of power to charge some capacitors and end up flickering the light on and off... quite annoying.

This discharging may shorten the life of the timer and most definitely will reduce the lifespan of the CFL.

You can get digital timers that are approved for inductive loads, they usually use an AAA battery to power the timer and have a relay that turns on and off any load.
 
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