Rohde TC 304, Instruction Manual

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Event E A1 · Error on sensor input
An error on the sensor input causes the controller to switch off (e.g. overflow in
measuring range). The error will only be reset when a program is restarted.
Possible causes:
• Thermocouple or wiring interrupted
• Maximum temperature of the controller has been exceeded
• Thermocouple reversed (temperature display “UNDER”)
Event E A3 · Safety circuit operational
When the maximum program temperature is exceeded by more than 20°C, the
safety circuit becomes operational, and switches the kiln off. This prevents your kiln
from overfiring.
Possible causes for over-temperature:
• Kiln safety contactor stuck in “ON” position
• Contactor is permanently operational
Event E A4 · Heating rate too low on full power
This error message refers to a kiln problem.
Possible causes:
• Defective mains fuse or phase, broken heating elements
• Heating elements too old (high temperatures)
• Thermocouple or thermocouple wiring short-circuit
• Defective contactor (often occurs during firing process)
Event E A5 · Kiln does not follow programmed heating rate
Other than Event A4, values for the heating rate have been set too high and the kiln
cannot follow the programmed values. This message is displayed only if enabled
in the configuration.
Event E A8 · Rate has been continued automatically
If the kiln cannot follow the heating rate, the ramp up is stopped. If the controller
finds the kiln is unable to catch up with the temperature the firing will continue, and
this message will be displayed for one minute.