Thermo Scientific System IV, Installation, Operation, Basic Maintenance

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Temperature Controller
The microprocessor controller controls temperature using a PID (Propor-
tional-Integral-Derivative) algorithm. It is designed with self-diagnostic
features and easy to use operator interface.
NEXT ENTER
Use this key to accept and save changes.
YES,
This key is used to increase numerical values.
NO,
This key is used to decrease numerical values.
When the controller is powered it displays the reservoir fluid temperature.
Press the
NEXT ENTER
key to view the setpoint. The display flashes
between
SP
and the actual setpoint number. If desired, use the
YES
and
NO
keys to change the setpoint. The display flashes as soon as either key is
depressed. Once the desired setpoint is displayed, press
NEXT ENTER
.
When selecting an operating temperature, remember that the lowest achiev-
able temperature is a function of the available flow rate, the temperature of
the cooling water supply and the heat load.
The temperature control system actuates a control valve in the FACILITY
WATER line. The control valve adjusts the flow of the cooling water supply
to produce the desired operating temperature.
NOTE:
The controller does not use the new value until the
NEXT ENTER
key is depressed and the display stops flashing. The controller will not allow
you to enter a value above the maximum or below the minimum value, or
any illegal value. If you try to enter an illegal value the display will revert to
its original value when the last digit was entered.
If the
NEXT ENTER
key is not depressed within one minute, the controller
will time out and the new value will not be accepted. The controller will
revert to the previous value.
NOTE:
Error codes are addressed in Section VI, Troubleshooting.