Chemglass CG-15001 Series User Manual
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The Chemglass Digital Temperature Controller can heat in either of two (2) Operating Modes, PID (Proportional, Integral, and
Derivative) or On/Off Mode. The difference between them is how they supply power to the heater.
In On/Off Mode, the Controller supplies power (ON) to the heater when the measured temperature is below the set point, and
does not supply power (OFF) to the heater when the measured temperature is above the set point. V
ery simply, it turns “on” when
below and “off” when above. The problem or disadvantage with this mode is that depending on the Heating Element used, the
process temperature may overshoot the set point by a significant margin (>30
). For example, if using a heating block, due to the
mass of the block, it will maintain heat and the temperature will continue to rise after the set point has been reached. Therefore,
the medium may be above temperature for an unacceptable period of time. In contrast, a Heat Lamp will begin to cool
instantaneously, so the overshoot margin would be minimal and may be acceptable. The On/Off Mode requires no tuning.
In the PID Mode the Controller monitors the rise in temperature during initial warm up and decreases power to the heater before
the set point is reached so that there is minimal overshoot. PID mode also adjusts the percent of time the heater is on so that the
set point is maintained accurately. The advantage of PID is that it delivers stable temperature control for virtually any heater type.
The disadvantage is that the Controller must be properly tuned to the parameters of the heater.
ON/OFF Mode of Operation
The Controller is configured in the PID Mode at the factory. However, it can be changed to run in the ON/OFF Mode. Use the
following sequence to set the Controller to run in the ON/OFF Mode.
1. Press and hold in both the and
keys until the word “tunE” appears in the display, then release both keys.
2. Press the
key until the letters “CyC.t” appear in the display.
3. While holding in the key, press the
key until the letters “on.of” appear in the display. Note: if the letter “A” is
displayed when the is pressed, then press the
key until “on.of” is displayed then release both keys.
4. Press the
key until the word “bAnd” is displayed.
5. While holding in the key, press the
key until the value “0.1” appears in the display, then release both keys.