GE CTR 80 - Manual (Page 49)

The calibration parameters R
0
, ALPHA, DELTA, and BETA characterize the
resistance-temperature relationship of the platinum control sensor. These pa-
rameters may be adjusted by an experienced user to improve the accuracy of
the bath.
9.11.1 Hard Cutout
This parameter is the temperature above which the unit shuts down automati-
cally. The parameter is set at the factory to approximately 120°C and can be
changed only through the variable resistor. This parameter cannot be changed
through the instrument menu or the communications port and is user settable.
9.11.2 R
0
This probe parameter refers to the resistance of the control probe at 0°C. The
value of this parameter is set at the factory for best instrument accuracy.
9.11.3 ALPHA
This probe parameter refers to the average sensitivity of the probe between 0
and 100°C. The value of this parameter is set at the factory for best instrument
accuracy.
9.11.4 DELTA
This probe parameter characterizes the curvature of the resistance-temperature
relationship of the sensor. The value of this parameter is set at the factory for
best instrument accuracy.
9.11.5 BETA
This probe parameter characterizes the low temperatures. The value of this pa-
rameter is set at the factory for best instrument accuracy.
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9 Controller Operation