On 9/1/2010 10:54 AM, Dwayne Reid wrote:

> Anyway, the flame is ignited with a spark gap fed from a standard
> spark ignition transformer such as those used in natural gas
> appliances.  The spark is monitored with a commercial flame control
> system that uses a UV sensitive sensor.
>
> The problem is with the UV flame sensor.  Its actually quite
> sensitive and can get false-triggered even when there is no spark if
> the system is being used outdoors.  That's causing us some grief.
>
>
> What I want to do is change to using a system that monitors the spark
> directly.  That is: it would monitor for spark current in the ground
> electrode.  If spark is present, fuel flow is enabled.
>
> This system uses continuous spark - the spark is operating anytime
> flame is being called for.  That makes spark proving a viable option
> for safety.
>
> The problem is that I can't find any spark proving systems that don't
> rely on a UV sensor.  That might be because I'm using the wrong
> search term ("spark proving" or "spark proving system") or it might
> be because I'm looking in the wrong places.

It may be hard to find because it is an indirect measurement of flame=20
presence. It only tells you if spark current is going somewhere.  A=20
fault in the HV cable insulation allowing a spark to ground won't be=20
detected and in that case there will be no spark at the ignitor.

What brand is the uv flame sensor?  I have a Hamamatsu "R2868 FLAME=20
SENSOR UV TRON=AE R2868" that works fine in broad day light - in direct=20
sun light, it does not fire.  But a BIC lighter at 15 feet away is detected=
..
--=20
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