Lakeshore 332 User Manual page 64

Control Setup (Continued)
The control setpoint can be displayed and set in temperature or sensor units. Changing setpoint units
does not change operation of the controller, only the way the setpoint is displayed and entered. A valid
curve must be assigned to the control input to use temperature units. To change setpoint units press
the Control Setup key and press Enter until the following display appears.
Use the s or t key to cycle through the following setpoint units: Temp K, Temp C, and Sensor, where
K = kelvin, C = degrees Celsius, and Sensor = volts (V) or ohms (Ω). Press the Enter key.
The Model 332 has two control modes, Closed loop and Open Loop. Closed-loop control, often called
feedback control, is described in Paragraph 2.6 of this manual. During closed-loop control operation the
Control Input, Setpoint, Heater Range, PID and Manual Heater Power (MHP) output parameters are
active. Open-loop control mode allows the user to directly set the heater output for Loop 1, control
output for Loop 2 with the MHP Output parameter. During Open-loop control only the heater range and
MHP Output parameters are active. To change Control Mode press the Control Setup key and press
Enter until the following display appears.
The Power Up setting refers to how the control output will respond after the instrument is powered
down. Power Up Enable means the controller will power up with the control output in the same state it
was before power was turned off. Power Up Disable means the controller will always power up with the
heater off no matter how it was set when power was turned off. To change the Power Up parameter
press the Control Setup key and press Enter until the following display appears.
Use the s or t key to toggle between Power Up Enable or Disable. Press the Enter key.
The Model 332 will display the heater output as either percent of full scale current or percent of full
scale power for the heater range selected for Loop 1. For Loop 2 the control output is always reported
in percent of full scale voltage and this parameter will not appear in the Control Setup menu. This
parameter affects the heater output display and the scale of the Manual Heater Power (MHP) output
parameter for Loop 1. The MHP Output scale is always the same as the control output display. To
change control output units press the Control Setup key and press Enter until the following display
appears.
Use the s or t key to toggle between Heater Out Power or Current. Press the Enter key.
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Lake Shore Model 332 Temperature Controller User's Manual
Select for Loop 1 °®
SP Units
Select for Loop 1 °®
Control Mode
Select for Loop 1 °®
Power Up
Select for Loop 1 °®
Heater Out
Temp K
Closed
Disable
Power
Operation