Chemglass CG-15001 Series - Manual (Page 4)

4
T T U U N N I I N N G G
Tuning is the process that matches the control characteristics of the controller to the heating characteristics of the heater. The
controller is said to be tuned to the heater when its memory is programmed with values telling it how fast the heater warms up,
cools off, and how efficiently it transfers heat.
For example, consider the difference between a heat lamp and a heating mantle. When electricity is applied to a heat lamp it
begins to heat instantaneously, and when it's turned off it stops heating instantaneously. In contrast, a heating mantle may take
several minutes to begin heating when electricity is applied and even longer to start cooling when electricity is turned off. Your
controller can typically regulate both a heat lamp and a heating mantle to +/- 1
C.
The Controller must be programmed with the time constants, which control how fast the heater heats when electricity is turned on,
and how fast it begins to cool when it is turned off. These time constants are called the tuning parameters. Every type of heater
has its own unique set of tuning parameters. For the controller to heat with stability, it must be programmed with the tuning
parameters for the heater currently being used. Tuning parameters for Heating Mantles were programmed into the controller at the
factory to maximize heating performance.
Tuning is regulated by five (5) of the temperature controller‟s user programmable functions. The correct value for these five (5)
functions can be calculated and loaded by the user manually, or the controller can do it automatically with its autotune feature.
Auto Tuning
1. Set up the equipment in the exact configuration it will be used. For example, to tune to a vacuum oven, place the
thermocouple in the room t emperature oven and plug the oven cord into the controller‟s 120VAC power receptacle.
NOTE: If the oven (or heater) has its own thermostat or power control, turn both to the highest limit.
2. Turn the controller and heater on, and enter the desired set point temperature. Press and hold the  key, then press 
key to increase or, press  key to decrease set point.
3. Press and hold in the  and  keys on the Controller until “tunE” is displayed then release both keys.
4. Press the  key (5 times) until “CyC.t” is displayed.
5. Press and hold the  key, simultaneously press the  key. Hold both keys in until the display reads “A-- “, or “A##”
where “##” is some number.