Lake Shore 370, Руководство пользователя

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Lake Shore Model 370 AC Resistance Bridge User’s Manual
4.11.4 Manually Setting PID Values
When operating the Model 370 as a temperature controller in closed loop PID mode, proportional (P), integral (I) and
derivative (D) parameter values must be properly selected to tune the control loop. Chapter 2 of this manual describes the
principals of closed loop (feedback) control including some tuning suggestions. PID values may need to change any time
the control temperature, cooling power or heater range change. Once parameter values are determined for several
temperatures they can be entered into the zone table and recalled automatically as described in Paragraph 5.3. The
manual output parameter can also be used during closed loop control but it should be set to zero for normal tuning.
4.11.4.1 Manually Setting Proportional (P)
The proportional parameter (also called gain) is the P part of the PID equation. It has a range of 0.001 to 1000. The
default value for P is 10. To begin control PID setting sequence press the
PID
key. The first PID setup screen appears as
a prompt for a P value.
PID Setup
Enter A Value For
Proportional (P): 10.000
Use the data entry keys to enter a proportional value between 0.001 and 1000. Press
Enter
to accept the new selection
and continue to the next setting screen. Press
Escape
to restart the setting sequence and enter a new value. Press
Escape
again to cancel the sequence and return to the normal display.
4.11.4.2 Manually Setting Integral (I)
The integral parameter (also called reset) is the I part of the PID equation. It has a setting range of 1 to 10,000 seconds.
A setting of zero turns I off. The default value for I is 20 seconds. The next PID setup screen appears as a prompt for an I
value.
PID Setup
Enter A Value For
Integral (I): 20.000 s
Use the data entry keys to enter an integral value between 1 and 10,000 or zero for off. Press
Enter
to accept the new
selection and continue to the next setting screen. Press
Escape
to restart the setting sequence and enter a new value.
Press
Escape
again to cancel the sequence and return to the normal display.
4.11.4.3 Manually Setting Derivative (D)
The derivative parameter (also called rate) is the D part of the PID equation. It has a setting range of 1 to 2500 seconds.
A setting of zero turns D off. The default value for D is zero (off). The next PID setup screen appears as a prompt for a D
value.
PID Setup
Enter A Value For
Derivative (D): 0.0000 s
Use the data entry keys to enter a derivative value between 1 and 2500 or zero for off. Press
Enter
to accept the new
selection and return to the normal display. Press
Escape
to restart the setting sequence and enter a new value. Press
Escape
again to cancel the sequence and return to the normal display.
4-20 Operation