"Dave" writes:

"Dave" wrote in message
ca...

"Samuel M. Goldwasser" wrote in message
...
PeterD writes:

On Thu, 11 Feb 2010 08:22:52 -0600, "Dave" wrote:

Does the "starter" continue to function once the lamp is going, or does
it
"drop out"? Just wondering. I fixed my MIL's light by replacing the
defective coil being driven by the SIDAC NTE6419, but wife is worried
that
I'm going to burn her mom's house down. I put a larger coil in, and it
is
brighter than it was, so she is worried that it will overheat and catch
fire. I tell her not to worry cause if it overheats the SIDAC will
fail,
shutting the whole system down. But if the "starter" (labeled
"ignitor")
only comes on for a few seconds to get the lamp going, that would be
better
than ever.

Thanks for any feedback,

Dave

In the diagram at http://en.wikipedia.org/wiki/Sodium-vapor_lamp, near
the middle of the web page, please point out the 'starter' or
'igniter'? Most HPS lamps have just a ballast and the lamp bulb, at
least the ones I see.

Personally I'd strongly recommend not replacing the balast with
anything other than the properly designed balast, matched to the bulb.
Since you have made this change, I'd agree with your wife: the lamp is
likely unsafe and probalby should not be used.

And replacing the ballast with a different one has what to do with the
(mythical) starter? That leaves me confused...

Agreed.

And especially, no modification should be allowed that increases the
brightness of the lamp unless the lamp is confirmed to be operating at
the
spec'd current. Presumably in this case, it there was some other
problem resulting in reduced current. Brighter lamp - higher
temperature,
which can result in a quick failure, hopefully not very explosively.

If there is no external igniter circuit, there may be one built into
the lamp.

Don't believe everything you read in Wikipedia.

--
sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/

Hey all,

Thank you very much for the input, first of all. Secondly, I posted a
JPEG of the starter (labeled "ignitor" on the cannister which holds the
PCB and ciruit I am about to referrence) to ABSE on 2/2/10 at 3:30 PM.
There pictured is the (failing) blue choke I replaced with a larger choke.
The one I took out *looked* like it might be a 60 or 75 uH choke, and I
put first a 100 uH choke in its place, and finally a 130 uH that would
just barely fit into the (plastic) cannister. In testing, the choke did
not seem to generate any heat, and my logic was as follows: if it did
cause the starter (ignitor) to overheat it would bring about the demise of
the NTE2419 SIDAC bi-directional thyristor diode immediately to it's side
(on the right in the JPEG) thereby shutting down the circuit. Below the
PCB (in the JPEG) is the ballast, which I did nothing with. Since I was
replacing a passive component with a passive component, I wasn't too
worried. Burn-in did not raise any suspicions (1/4 hour of operation in
my workshop). I would send more photos (and try again to figure out this
damn camera) but the light is currently in use. The experimenting I did
with the light only seemed to show that a lower inductance choke resulted
in a more "yellow" illumination, and a higher inductance gave a "whiter"
light. I can bring it down if there is truly cause for concern, just hate
to do so unnecessarilly. And there is nothing in the diagram referrenced
above like the small circuit I was working on inside the cover of the
lamp. Don't know what to think about that...

Thanks,

Dave

PS: Burn in was a 1/2 hour operation in my workshot, not 1/4 hour, as
written above. My bad. Sorry.

Sorry, where did you post the JPEG of your circuit?

Changing anything in the starter shouldn't affect how the lamp runs.

--
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