Compact Fluorescent Lamp - switch on current ?

N_Cook

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Jul 24, 2008, 11:23:51 AM7/24/08

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15W filament lamp controlled by a tiny reed relay, on for a total of a
couple of hours a day. Been in use for 20 years or so. Decided to replace
the working 15 filament one with a 11W CFL but on first switch on, the
contacts ,presumably only 0.5A rating or so, held on at switch off.

A slight tap releases them but of course no good with continued CFL use
unless uprating the relay. Previously stuck contacts occured 10 years or so
back when the first 15W bulb blew, plasma arc current at failing switch-on
presumably.

What is the switch on current of CFLs compared to conventional just out of
interest ?

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/

Peter Dettmann

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Jul 24, 2008, 7:28:35 PM7/24/08

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On Thu, 24 Jul 2008 16:23:51 +0100, "N_Cook" <div...@tcp.co.uk>
wrote:

>15W filament lamp controlled by a tiny reed relay, on for a total of a
>couple of hours a day. Been in use for 20 years or so. Decided to replace
>the working 15 filament one with a 11W CFL but on first switch on, the
>contacts ,presumably only 0.5A rating or so, held on at switch off.
>
>A slight tap releases them but of course no good with continued CFL use
>unless uprating the relay. Previously stuck contacts occured 10 years or so
>back when the first 15W bulb blew, plasma arc current at failing switch-on
>presumably.
>
>What is the switch on current of CFLs compared to conventional just out of
>interest ?

Only proerly designed "power reed" contacts are suitable, a the normal
reeds are not any good for currents at amp levels. Having said
that, most CFL's have a limiting resistor input, so the input will not
be more than a few amps.

Peter

Archon

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Jul 24, 2008, 7:37:39 PM7/24/08

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Stick to the 15W filament, your chinese made CFL will only last 8 months
before it overheats, blows your relay and dies, costing you 10 times the
filament lamp. Surge current on a 22w CFL is 1.5A

Franc Zabkar

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Jul 25, 2008, 1:14:48 AM7/25/08

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On Thu, 24 Jul 2008 16:23:51 +0100, "N_Cook" <div...@tcp.co.uk> put
finger to keyboard and composed:

>15W filament lamp controlled by a tiny reed relay, on for a total of a
>couple of hours a day. Been in use for 20 years or so. Decided to replace
>the working 15 filament one with a 11W CFL but on first switch on, the
>contacts ,presumably only 0.5A rating or so, held on at switch off.
>
>A slight tap releases them but of course no good with continued CFL use
>unless uprating the relay. Previously stuck contacts occured 10 years or so
>back when the first 15W bulb blew, plasma arc current at failing switch-on
>presumably.
>
>What is the switch on current of CFLs compared to conventional just out of
>interest ?

Here are several reverse engineered CFL circuits:
http://www.pavouk.org/hw/lamp/en_index.html

The author writes ...

"During start is peak collector current about 3 to 5 times bigger than
during normal operation."

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.

GregS

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Jul 25, 2008, 8:47:48 AM7/25/08

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I was turning a lamp off then on above the sink which normally runs 24-7.
There was a really big arc, but I don't remember if it was while
turning off or on. I have 6 outside CFL's on one switch. Never heard any
arc on that.

I understand that they can draw a lot more current near the end of their
life.

greg

N Cook

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Jul 26, 2008, 7:41:15 AM7/26/08

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=Franc Zabkar <fza...@iinternode.on.net> wrote in message
news:130i8413aesdbmk63...@4ax.com...

Whatever technical stuff you ever wanted to know about CFLs on there