Power Recovery - Orton AutoFire Plus User Manual

AutoFire® Kiln Controller
POWER INTERUPTION RECOVERY
The AutoFire® Kiln Controller activates a Power Recovery feature when electric power to the controller has
been interrupted. The controller stores time and temperatures so it can determine the length of a power outage.
The Power Recovery feature works in the following way:
If the time is greater than one hour or the temperature drop is greater than 255°F, the controller terminates the
previous firing cycle and displays an error in the display (described below). If the difference between the final
programmed temperature and the last measured temperature is less than 100°F and the difference between the
last measured temperature and the current kiln temperature is greater than 100°F then the temperature drop is
considered to be too large at this stage of the firing so the controller terminates the firing cycle. Otherwise, the
controller compares the current temperature with the last measured temperature (prior to power loss) and
resumes the previous firing cycle as described below.
•
A new set point temperature is established from the current kiln temperature.
•
If the controller is to resume program operation of a ramp, the controller continues the ramp at the
rate as programmed.
•
If the controller is to resume program operation of a dwell, the controller ramps the temperature at
the programmed rate used to achieve that dwell temperature. Dwell time is not advanced during this
recovery ramp. When the dwell temperature is achieved, the dwell time is resumed.
See Flow Chart of Power Interruption Recovery on Next Page
Power Loss Error Messages
P1
If the difference between the previous valid temperature and the current kiln temperature is greater than 255°F
(142°C) then the controller terminates the firing cycle and displays the error code 'P1' in the display. To
acknowledge the error code, simply press 'STOP/START' to get back to IdLE mode.
P2
If the thermocouple failed just prior to the power loss, the controller will display the error code 'P2'. If once
the error code is acknowledged by pressing 'STOP/START' the display should show 'IdLE' and current kiln
temperature alternately. But for an open thermocouple the temperature would be replaced with four dashes
'- - - -' because a valid temperature would not register.
P3
If the duration of time since previous valid temperature is greater than 60 minutes then the controller terminates
the firing cycle and displays the error code 'P3' in the display. To acknowledge the error code, simply press
''STOP/START' to get back to IdLE mode.
User's Guide
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