Keithley TEC SourceMeter 2510, User Manual

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4-12 PID Control Concepts Models 2510 and 2510-AT User’s Manual
Basic autotune procedure
The general procedure below outlines the basic steps for using the autotune commands to
tune the PID loop. Keep in mind that this procedure is intended only as a starting point,
and some experimentation may be required to obtain the desired results.
1. Send the SOUR1:TEMP:ATUN:STAR command to program the start temperature
value. For example, the following command would set the start temperature to 45°:
SOUR1:TEMP:ATUN:STAR 45
2. Send the SOUR1:TEMP:ATUN:STOP command to program the stop temperature
value. For example, the following command would set the stop temperature to 50°:
SOUR1:TEMP:ATUN:STOP 50
3. Set the maximum temperature protection limit; for example:
SOUR1:TEMP:PROT:HIGH:LEV 50
4. Set the minimum temperature protection limit; for example:
SOUR1:TEMP:PROT:LOW:LEV 0
5. Set the maximum TEC voltage limit; for example:
:SOUR1:VOLT:PROT:LEV 2.8
6. Set the maximum TEC current limit, for example:
:SENS:CURR:PROT:LEV 1.2
7. If the system TAU is known to be greater than 100 seconds, send the
SOUR:TEMP:ATUN:SYSTAU MED command to allow for the slower system
response. If the system TAU is known to be greater than 200 seconds, send the
SOUR:TEMP:ATUN:SYSTAU LONG command to allow for the very slow system
response.
8. Initiate the autotune process by sending this command:
SOUR1:TEMP:ATUN:INIT
Command Description
:STOP? Query stop temperature value.
:INITiate Initiate autotune procedure.
:SYSTAU Program rate for SHOR, MED, or LONG Tau loads.
:SYSTAU? Query Systau value.
*Temperature value must be between the upper and lower temperature protection limits.
Table 4-3 (cont.)
Autotune commands