Dwayne Reid <dwayner <at> planet.eon.net> writes:
> I think that you are missing the point - there can't be any flame if=20
> there is no spark because without spark, the fuel supply must be disabled=
..

Hmm. I see, it is a chicken or egg problem in your case.
=20
> In other words, I have to prove that spark exists before the fuel=20
> supply is allowed to be enabled.

> The other requirement is that the spark proving system must be=20
> approved by either CSA or UL.  I can't 'roll my own' system without=20
> submitting it for approval.

Can't you cheat a little? Use a certified IPI controller and your system
too, on top of it?  I mean the requirement is for the pilot igniter to
be always on but if you provide a second igniter for the main flame
you are still within specs as far as the regulator is concerned no? In
fact you would be over-engineering the system?

I mean have a normal IPI and its spark gap and pilot light, and its
main gas valve control output enabling a main gas valve and your system
modulating a second fast gas valve after it and igniting it supplementarily
with a second spark gap.
=20
> That's what it looks as if we are going to have to do.  Design it,=20
> make sure that it works properly, then pony up the several thousand=20
> dollars for certification.

That looks expensive. Also it would have to be done for each country afaik.

-- Peter

--=20
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