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controllers

updated fri 24 sep 04

 

WHC228@AOL.COM on thu 23 sep 04


Ron
It has been my experience that controllers using K type thermocouples are
usually wrong after they have been fired a few times.
My suggestion to anyone that is serious about using their kiln with a
controller is to buy S type couples and have their controller reset to use them.
I have thermocouples that are fifteen years old that work perfectly, even
after they went through a fire that destroyed the building that they were in.
K type couples have a predictable life at the various usage's. Higher temps
and they fall off pretty fast, and at low temps such as cone 06 they last a
long time.
The problem is that even if you recalibrate your K type couple, it will need
to be recalibrated in a short time. They are just are not reliable.
It will cost about $100 each for the S type Thermocouples from a place like
Cleveland Electric Labs in Cleveland Ohio. That will include the protective
cover and the nice hookup for the electrical connection.
Once your program is set with these couples your programmer will be exact
every time.
Cone are a function of both time and temperature, so the first firing or two
you will need to watch the results to make sure that your cones melt properly.
A lot of problems with the controllers are blamed on the controller, that
should be blamed on worn out elements.
If the elements aren't up to the job they will make the kiln lag and the
controller will not be able to do its job because the kiln just can't keep up.
I use a program from the controller people (Bartlett) called KISS.
This program will give you a lot more information about what is going on in
the kiln.
It supervises all three zones and will tell you if there is a zone that is
falling behind, and an element isn't doing its job. It will also show if the
kiln is really following the program.
When elements start to get old they slow down. The graph will tell you.
Lots of other good stuff in the program too.
Bill Campbell