Most LE bulbs seem to say: Not suitable for use with dimmers, time
switches or photo cells.

I can understand they are not suitable for dimmers, but what is wrong
with having a time switch or dawn-to-dusk switch turn such bulbs on and
off?
--
Les Desser
(The Reply-to address IS valid)

Les Desser wrote:
Most LE bulbs seem to say: Not suitable for use with dimmers, time
switches or photo cells.

I can understand they are not suitable for dimmers, but what is wrong
with having a time switch or dawn-to-dusk switch turn such bulbs on and
off?

This is because some of these devices need power themselves, and some of
them draw power by passing a tiny current through the bulb all the time,
which would cause a LE lamp tp flash every now and then.

If you have a time switch or dawn-to-dusk switch that clicks when it
turns to load on and off, then this will probably be OK.

Toby...

In article ,
Les Desser wrote:
Most LE bulbs seem to say: Not suitable for use with dimmers, time
switches or photo cells.

I can understand they are not suitable for dimmers, but what is wrong
with having a time switch or dawn-to-dusk switch turn such bulbs on and
off?

Not really to do with the CFL but the design of the time switch, etc. Many
of these are designed to replace a simple light switch so get their
neutral feed to their electronics via the tungsten lamp filament. The
current is so low that the ordinary bulb doesn't light up. But a CFL
doesn't have the same low 'not in use' resistance - so strange things
could occur. It's easy enough to switch CFLs with any of these devices but
involves some rewiring to provide a dedicated neutral to the switching
device and a mechanical relay to do the switching - the coil of the relay
replacing the tungsten lamp.

--
*OK, so what's the speed of dark? *

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
Les Desser wrote:
Most LE bulbs seem to say: Not suitable for use with dimmers, time
switches or photo cells.

I can understand they are not suitable for dimmers, but what is wrong
with having a time switch or dawn-to-dusk switch turn such bulbs on and
off?

In article , "Dave Plowman (News)"
Sun, 21 Jun 2009 18:34:59 writes

Not really to do with the CFL but the design of the time switch, etc. Many
of these are designed to replace a simple light switch so get their
neutral feed to their electronics via the tungsten lamp filament. The
current is so low that the ordinary bulb doesn't light up. But a CFL
doesn't have the same low 'not in use' resistance - so strange things
could occur. It's easy enough to switch CFLs with any of these devices but
involves some rewiring to provide a dedicated neutral to the switching
device and a mechanical relay to do the switching - the coil of the relay
replacing the tungsten lamp.

Thank you and Toby for your clear responses which confirms what I
thought - that for "proper" circuits there should be no problem.

--
Les Desser
(The Reply-to address IS valid)

"Dave Plowman (News)" wrote in message
...
In article ,
Les Desser wrote:
Most LE bulbs seem to say: Not suitable for use with dimmers, time
switches or photo cells.

I can understand they are not suitable for dimmers, but what is wrong
with having a time switch or dawn-to-dusk switch turn such bulbs on and
off?

Not really to do with the CFL but the design of the time switch, etc. Many
of these are designed to replace a simple light switch so get their
neutral feed to their electronics via the tungsten lamp filament. The
current is so low that the ordinary bulb doesn't light up. But a CFL
doesn't have the same low 'not in use' resistance - so strange things
could occur. It's easy enough to switch CFLs with any of these devices but
involves some rewiring to provide a dedicated neutral to the switching
device and a mechanical relay to do the switching - the coil of the relay
replacing the tungsten lamp.


The other trick which allows the use of such bulbs with these devices is to
wire a resistor in parallel with the bulb holder. The resistor gives the
'not in use' resistance formerly provided by the bulb.

In article ,
Calvin Sambrook wrote:
The other trick which allows the use of such bulbs with these devices is
to wire a resistor in parallel with the bulb holder. The resistor gives
the 'not in use' resistance formerly provided by the bulb.

Snag with that is it will waste energy when the thing switches on.

--
*The e-mail of the species is more deadly than the mail *

Dave Plowman London SW
To e-mail, change noise into sound.

On Jun 22, 11:11*pm, "Dave Plowman (News)"
wrote:
In article ,
* *Calvin Sambrook wrote:

The other trick which allows the use of such bulbs with these devices is
to wire a resistor in parallel with the bulb holder. *The resistor gives
the 'not in use' resistance formerly provided by the bulb.

Snag with that is it will waste energy when the thing switches on.

Lets see
The options:
1. filament lamp - much worse energy wise, maybe 45w wasted
2.CFL with R, 1w wasted
3. CFL with no R - same energy waste when off, no waste when on
4. PIR with relay & CFL - same energy use when off, 1w lost in the
relay coil when on

The only way I see to improve on the loss of a resistor is to fit a
capacitor instead.


NT

You can get a capacitor that you wire in parallel with the low energy bulb
which allows enough electricity through to power up the dusk to dawn switch.

http://www.tlc-direct.co.uk/Products/SMFLA01.html
Bit bloomin steep if this is a capacitor, I am sure I only paid £2 for mine,
pushed in into ceiling cavirty behind ceiling rose.

Downside is the low energy bulbs flicker faintly when off and from what I
have read some types of low energy bulbs glow permenantly and have seriously
shortened lifetimes.


"Les Desser" wrote in message
...
Most LE bulbs seem to say: Not suitable for use with dimmers, time
switches or photo cells.

I can understand they are not suitable for dimmers, but what is wrong with
having a time switch or dawn-to-dusk switch turn such bulbs on and off?
--
Les Desser
(The Reply-to address IS valid)

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Ian_m coughed up some electrons that declared:

You can get a capacitor that you wire in parallel with the low energy bulb
which allows enough electricity through to power up the dusk to dawn
switch.

http://www.tlc-direct.co.uk/Products/SMFLA01.html
Bit bloomin steep if this is a capacitor, I am sure I only paid £2 for
mine, pushed in into ceiling cavirty behind ceiling rose.

Downside is the low energy bulbs flicker faintly when off and from what I
have read some types of low energy bulbs glow permenantly and have
seriously shortened lifetimes.


Megaman have dimmable CFLs, designed to work with regular dimmers.

Might be worth looking at?