Section Iv Operation; Start Up; Controller Keypad & Display - Thermo Scientific ULT-80 Installation & Operation Manual

Section IV Operation

Start Up

Before starting, check all electrical, plumbing, and inlet/outlet connections; and
make sure the work area has been properly filled with bath fluid.
To start the bath, place the MAIN ON/OFF switch to the ON position. The
pump will start and the controller will display the temperature of the fluid in the
reservoir. (The controller may display Er21 until the reservoir fluid tempera-
ture drops within 5°C of the circulator's high-end temperature range, see page
16.) To start the refrigeration system place the REFRIGERATION ON/OFF
switch to the ON position.
NOTE: For high-temperature circulators the refrigeration automatically shuts
down above 35°C. The light in the REFRIGERATION ON/OFF switch will also
extinguish. If rapid cool down is needed above 35°C immerse a tap water
cooling coil into the reservoir. Either of these methods can also be used to
increase stability.
Once the cooling system has been turned off, it should remain off for approxi-
mately 10 minutes before attempting to restart. Failure to allow this time for
pressure equalization within the refrigeration system could cause the com-
pressors to cycle on their overloads.
Controller Keypad
& Display
The microprocessor controller maintains temperature using a Proportional-
Integral-Derivative (PID) algorithm. It is designed with self-diagnostic features
and easy to use operator interface.
The controller's HEAT indicator shows the status of the heater. The HEAT
indicator is lit when the heater is on. The HEAT indicator flashes when the
heater is pulsating.
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