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FAIL
- This alarm will appear during an active firing and indicates that the
thermocouple sensor is no longer detected. The signal was lost during and the
firing was terminated. The controller can not operate without a thermocouple
signal. In most cases, the thermocouple has failed and will need replacement, or the
electrical connections for the thermocouple may be loose or damaged. Check the wiring
for the thermocouple and the physical condition of the probe inside the firing chamber.
FtL
- This alarm indicates that the firing was taking too long to complete and the firing
was terminated. The controller monitors the deviation from the desired firing schedule as
compared with the actual firing results. There are 2 conditions for the
FtL
alarm.
1. The heating or cooling rate is slower than 27°F (15°C) per Hour
2. The current program step has lasted 2 hours longer than anticipated.
In most cases, the
FtL
alarm occurs during heating if the heating rate is set to a fast
speed that cannot be maintained by the kiln. If the heating rate is within the systems
capability, a component failure has probably occurred with the heating elements or the
heater relays.
During cool-down, a well insulated system will have cooling limitation and rapid cooling
rates may set off this alarm if the cooling speed cannot be maintained. Increasing the
final cool-down temperature or slowing the programmed cooling rate can avoid this
alarm.
tCL
- This alarm indicates that the thermocouple signal is not responding to the
demand for more system power during heat-up. There are 3 conditions for the
tCL
alarm.
1. The heating rate is slower than 9°F (5°C) per Hour
2. The actual kiln temperature is lagging behind the desired setpoint temperature by
more than 100ºF (56ºC).
3. The actual temperature is less than 500ºF (260ºC)
In all cases, the
tCL
alarm occurs during heating when little temperature rise is detected.
This can be the result of a component failure; most likely a failed heating elements or a
heater relay. Another possible problem is with the thermocouple sensor signal; if the
thermocouple probe is not properly positioned in the firing chamber or if the wiring from
the thermocouple has short-circuited the controller will not detect actual temperature
changes in the firing chamber.
EtH
- This alarm indicates that the Electronics temperature is too hot for controller
operation. The controller temperature must be below 176ºF (80ºC) to prevent damage to
the electronic components. The
EtH
alarm cannot be cleared unless the board
temperature has cooled. If the
EtH
occurs frequently, check the kiln for heat loss near
the controller. Proper venting and heat-shielding should be inspected.
HtdE
-The High Temperature deviation alarm sounds an audible alarm and terminates
the firing if the actual kiln temperature is above the controller set-point by 56ºC (100ºF).
This alarm is active only when the actual kiln temperature is above 500ºF (260ºC)
