Switch timer does not work with flourescent bulb?
 

Is there a problem using a switch timer with a flourescent long-life
bulb? I have had 2 timers do strange things when I replaced an
incandescent bulb with a flourescent. The timer seems to turn on the
light during the day instead of at night. It works fine for a couple
of days, then gets confused with the timer settings.
Thanks
Mark Sabatini

Switch timer does not work with flourescent bulb?
 

Switch timer does not work with flourescent bulb?
 

Is there a problem using a switch timer with a flourescent long-life
bulb? I have had 2 timers do strange things when I replaced an
incandescent bulb with a flourescent.

Such timers ought to have a sticker or notice "incadescent use only"
because they rely on a trickle of current
thru the "off" lamp to run the timer circuit
(rather than using a third wire to supply its own power).

Switch timer does not work with flourescent bulb?
 

Switch timer does not work with flourescent bulb?
 

On Jan 16, 2:57*am, wrote:
wrote:
Is there a problem using a switch timer with a flourescent long-life
bulb? I have had 2 timers do strange things when I replaced an
incandescent bulb with a flourescent. The timer seems to turn on the
light during the day instead of at night. It works fine for a couple
of days, then gets confused with the timer settings.

Yes, the cheaper models say "for incandescent lamps only" or words to
that effect. *I found a more expensive timer that clearly uses a relay
internally and has a battery to power it and I guess the clock circuitry
as well. *The timer I replaced started losing track of time when I
switched to CFLs for my outdoor porch lights. *I think the CFLs put
some high frequency noise on the circuit which confuses a clock chip
that uses the 60Hz line frequency as a reference. *The better model
says it can be used with electric motors as well.

Bill Ranck
Blacksburg, Va.

Another suggestion/idea.
Some of those timers (electronic ones) may depend (as do some
thermostats) on sufficient 'juice' flowing through, even during the
period of time when the timer is 'off', to operate the timing
circuits, within the unit itself, correctly.
While that current may be only need to be a few milliamps, a CFL lamp,
which even when on uses much less current than an incandescent bulb,
may not be allowing sufficient 'minimum' current flow during the 'off'
cycle to keep the timer operating consistently?
It may well be as someone mentioned also that such timers are best (or
must be) used with incandescent lamp bulbs. All these additional 'add-
on' items, often available cheaply at hardware and other stores are
not necessarily compatible with each other! In fact some are downright
unsatisfactory in that they, if cheaply made, either can't do the job
or may generate radio/TV interference. Some dimmers are notorious for
that, for example.