On 2011-01-03, Gunner Asch wrote:

[ ... ]

Programming can be simple..or a stone bitch..depending on how many set
points..ups and downs and delays for the particular treatment you are
trying to do. 800f for 20 minutes..rise to 1487F for 2 hours, drop to
450F for 30 minutes..up to 2200f for 4 minutes....chuckle..it can do
it..but it confuses the **** out of me. Fortunately Im doing single set
point heat treat...Up to 1400F for an hour and then off as an
example...G Whew!!

The problem with *my* oven at least with that kind of cycle
would be just how fast does the temperature need to fall vs how fast
will it *really* fall with the existing oven. Faster with the oven door
open and a fan blowing into it, but no way to be sure just what the
cooling rate of the workpiece vs the theromcouple.

Of course, my (older) Omega controller has the disadvantage of
having a single set point. But it has the advantage of a low voltage DC
output to feed to a solid state relay to control the power to the
heating element, so it is reliable and quiet as it cycles. :-)

Enjoy,
DoN.

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