PAGE 14
T E C A L 4 2 5 H O P E R A T O R ’ S M A N U A L
Power Indicator
The top indicator shows that there is power to the unit
Power to the Block Indicator
The next indicator shows when there is power to the block.
When the set temperature is higher than the block temperature this indicator
will light. If the light is on continuously the heater is getting constant power.
The only exception is described under Over-Temperature Indicator. As the
temperature approaches the set temperature the indicator will flash. When
set temperature is reached the indicator will stay on for shorter periods. If the
block temperature is above the set temperature then the indicator will be off,
as the heater is not getting any power.
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 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 heater light is on (the light staying on or
not depends on which circuit has sensed a fault).
