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T E C A L 4 2 5 S O P E R A T O R ’ S M A N U A L
Over-Temperature Indicator
If the unit should, for any reason, exceed the temperature set for the over-
temperature cutout (see page 15), the over-temperature indicator will light.
The heater will have been switched off and the unit will begin to cool even if
the heater light is on (the light staying on or not depends on which circuit has
sensed an over-temperature).
Sensor fault Indicator
If the unit there should, for any reason, be a sensor fault, the bottom
indicator will light. The power to the block will have been switched off and
the unit will begin to return to ambient even if the power light is on (the light
staying on or not depends on which circuit has sensed a fault).
Setting the units for temperature
The unit will normally be set to display in °C, if you require it to work and
display in °F press both the
UP ARROW
and
DOWN ARROW
buttons at the
same time. To convert back, press both buttons again.
Setting the Operating Temperature
1.
To display the set temperature on the digital display, press and hold
the
SET
Temperature button.
To adjust the set temperature, press the
SET
Temperature button and
hold it while pressing the
UP
or
DOWN
buttons. When the
SET
Temperature button is released, the measured temperature is
displayed (in degrees Celsius).
2.
The heater (and heater indicator) comes on if the set temperature is
higher than the current block temperature. The fan will automatically
come on if the set temperature is more than 15°C below the actual
temperature of the block.
3.
When the measured temperature approaches the set temperature, the
heater indicator will begin to flash. As the measured temperature
stabilises the indicator will stay on for shorter periods.
4.
There will be a time-lag between the heater block and the insert
achieving the set temperature due to thermal contact between them.
The display may reach temperature in 2 or 3 minutes while the insert
may take 5 minutes or more to reach temperature.
