On Wed, 16 Mar 2005 21:19:47 GMT, "TKM" wrote:


"Victor Roberts" wrote in message
.. .
On Wed, 16 Mar 2005 03:28:59 GMT, "James Sweet"
wrote:


"JM" wrote in message
news:TrKZd.3545$ed6.456@trndny06...
quoting:
Are you claiming that your "ballast" has no inductor or no
capacitor?
That the only device connected between the lamp and the power line
is
a triac?

All I know is that the entire ballast is the size of a pack of
cigarettes -
I see no cap or choke of any size.

The inductor and capacitor used in 2-lamp T12 shoplight-type L-C
ballasts can easily fit into a package the size of a pack of
cigarettes.


Is this happen to be a "lights of America" shoplite BTW? Those things
pretty
much have what Vic had described (capacitor and small inductor) in
series
with the lamps. There is also a triac or triac-like switching device in
these LOA ballasts that rapidly switches the preheating of the lamp
electodes, and LOA marketed this as "instant start".


Sounds like a very cheap HF electronic ballast.

The ballast is not electronic - it is just a L and C. The starter is
electronic, but this is inactive once the lamp starts.

--
Vic Roberts
http://www.RobertsResearchInc.com
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Sounds also like a device that should have been built into the lamp itself
since its life is probably closer to the lamp life than to the life of the
usual commercial ballast. Wonder why we've not seen that for linear lamps
especially for residential applications.

The life of the ballast can be quite long as it is only an inductor
and capacitor. And, when you add to that the fact that this high
current crest factor ballast destroys lamps rather quickly, you can
see that the ballast should outlast many lamps :-)

--
Vic Roberts
http://www.RobertsResearchInc.com
To reply via e-mail:
replace xxx with vdr in the Reply to: address
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