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manual vice digital controller firing differenes?

updated tue 19 dec 00

 

Michael Haldiman on sun 17 dec 00


All,

As stated in an earlier post, we have just installed a new Orton controller and are also
experiencing slow (30F/hr or less vice the scheduled 108F/hr) ramp rates during the final
part of our Cone 6 firing. Our problem is not the elements or the availability of current,
but the cycling of the controller controlled relays.

According to AMACO, the proposed firing approach places their factory provided manual
switches on High (which removes their toggling and locks them full on) by the 5th firing
hour. The part that we don't understand is if the controller software is expecting a ramp
rate of 108F/hr and that rate is not being obtained (measured) - then why are the relays
still toggling?

Again we reflect back to our pre controller firings where our AMACO kiln fired to Cone 6 in
nine-ten hours / Cone 10 in eleven-twelve hours. Now with our new controller our Cone 6
firings are taking anywhere from 12 to 15 hours!

During these controller firings we monitored current draw (when the relays were allowed to
be on) and it was at the expected 15amps/per relay. But the best we found the controller
trying to allow our kiln to produce the proposed ramp rate was when their software locked on
the bottom relay, but kept toggling the middle and top relays. By the way - we know its not
just one controller because we swapped it our for a another and fired again with the same
length firing with relays still toggling!

We can only wonder what our firing time would be if our relays were "all" locked on during
the correct point of the proposed firing program and only toggled off with the ramp temp
"exceeded" the proposed rate?

Has anyone else tracked their firing ramp rates while using their digital controller? Did
they match the factory proposed rate? Did your new firing times match your "pre controller"
ones? If you previously fired to Cone 10, did your new controller still fire to Cone 10 or
did it fall short (shut off early) because of a poor ramp rate?

For now our local supplier (Dick @ ConeTen in St. Louis) is talking to Orton about their
controller software program and the problem we have found with all relays not fully locking
on. We'll let you know what turns up!

Hope others are having better luck!

Mike & Rose - Throwing in St. Louis ~