SRS Labs CTC100, User Manual

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Operation 38
CTC100 Programmable Temperature Controller
o wait for the temperature to re-stabilize before running the
autotuner again.
The autotuner disturbance size (Step Y) was not large enough to create a noticeable change
in the temperature.
The autotuner wait time (Lag) was not long enough for the heater to change the
temperature.
To determine the source of the problem, look at a dual plot with the heater output on one plot
and the sensor temperature on the other. Make sure that the temperature was stable before the
heater turned on and that it changed significantly after the heater was turned on.
Autotuning was cancelled because the PID mode was set to "Off"
The user turned off PID feedback while the tuner was running. The tuner is unable to run when
PID feedback is turned off.
Autotuning was cancelled because the PID mode was set to "Follow"
after autotuning started. The tuner is unable to run
in this mode.
Autotuning was cancelled because the tuning mode was set to "Off"
Indicates that the user turned off autotuning while it was running.
Tuning was cancelled because the input was disconnected
No sensor signal was detected during the tuning process. Ensure that a sensor is plugged in and
that its reading is not blank. If the reading is blank, an incorrect sensor range, sensor type, or
calibration may be selected.
Unable to tune feedback because the outputs are disabled. Press the
Output Enable button to enable outputs.
The outputs must be enabled before autotuning, or else the CTC100 will not be able to provide
any power to the heaters.
Unable to tune feedback because the heater is disconnected
This message appears when the heater is connected to channels Out 1 or Out 2 and the measured
heater resistance is less than 1 or greater than 10 k .
Unable to tune feedback due to a hardware fault in the heater output
This message appears when the heater is connected to channels Out 1 or Out 2 and one of the
following conditions occurs:
The current at the + and terminals is not equal
Current was detected when the heater was supposed to be off
The measured current differs from the expected current.
Make sure that the heater is not shorted to ground or to another power supply. In some cases,
this error message may indicate that the output circuit has been damaged.
Unable to tune feedback because the heater is under range
Unable to tune feedback because the heater is over range
During step response tuning, the heater output is increased by the amount shown in the
button. During relay tuning, the heater output is increased and then decreased by half of the Step Y
value. If the heater output is expected to exceed its maximum or minimum values, an error
message appears. The message appears before the heater output is changed.