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.

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