Rockwell Automation 900-TC32 Digital Temperature Controllers, Series B - Manual (Page 327)

Publication 900-UM007D-EN-E - January 2011
Parameter Functions & Definitions 5-99
Function: By setting the Automatic Cooling Coefficient Adjustment
parameter to ON, autotuning can be executed during heating/cooling control
to automatically calculate the cooling coefficient at the same time as the PID
parameters. If there is strong non-linear gain for the cooling characteristics,
such as when cooling water boils for cooling control, it may not be possible to
obtain the optimum cooling coefficient at the Controller, and control may take
the form of oscillating waves. If that occurs, increase the proportional band or
the cooling coefficient to improve control.
Related Parameter
• Cooling coefficient (Adjustment function group, page 5-36)
Heater Overcurrent Use (900-TC8, 900-TC16)
Conditions of Use: Heater burnout, HS alarms, and heater overcurrent
detection must be supported. Alarm 1 must be assigned.
Function: Configure this parameter to use the heater overcurrent alarm.
The PV rate of change calculation period can be set in units of 250 ms
(sampling period).
Heater Overcurrent Latch (900-TC8, 900-TC16)
Conditions of Use: Heater burnout, HS alarms, and heater overcurrent
detection must be supported (two CTs). Alarm 1 must be assigned.
Table 5.DT
Selections Default
on: Enabled, off: Disabled off
Table 5.DU
Selections Default
on: Enabled, off: Disabled on
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