Programming the HP E1415 for PID Control
91
can be used to specify how many updates you need to perform during phase
2 (UPDATE phase) and assigns a constant window of time to accomplish all
of the updates you will make. The default value for <num_updates> is 20.
Fewer updates (shorter window) means slightly faster loop execution times.
Each update takes approximately 1.4
µ
seconds.
To set the Update Window to allow 10 updates in phase 2:
ALG:UPD:WIND 10
allows slightly faster execution
than default of 20 updates
A way to synchronize variable updates with an external event is to send the
ALGorithm:UPDate:CHANnel ’<dig_chan/bit>’ command.
•
The <dig_chan/bit> parameter specifies the digital channel/bit that
controls execution of the update operation.
When the ALG:UPD:CHAN command is received, the module checks the
current state of the digital bit. When the bit next changes state, pending
updates are made in the next UPDATE Phase.
ALG:UPD:CHAN ’I133.B0’
perform updates when bit zero of
HP E1533 at channel 133
changes state
Enabling and
Disabling
Algorithms
An algorithm is enabled by default when it is defined. However, the
ALG:STATe <alg_name>, ON | OFF command is provided to allows you to
enable or disable algorithms. When an individual algorithm is enabled, it
will execute when the module is triggered. When disabled, the algorithm
will not execute.
NOTE
The command ALG:STATE <alg_name>, ON | OFF does not take effect
until an ALG:UPDATE command is received. This allows you to send
multiple ALG:STATE commands and then synchronize their effect.
To enable ALG1 and ALG2, and disable ALG3 and ALG4:
ALG:STATE ’ALG1’,ON
enable algorithm ALG1
ALG:STATE ’ALG2’,ON
enable algorithm ALG2
ALG:STATE ’ALG3’,OFF
disable algorithm ALG3
ALG:STATE ’ALG4’,OFF
disable algorithm ALG4
ALG:UPDATE
changes take effect at next
update phase
Setting Algorithm
Execution
Frequency
The ALGorithm:SCAN:RATio ’<alg_name>’,<num_trigs> command sets
the number of trigger events that must occur before the next execution of
algorithm <alg_name>. If you wanted PID ’ALG3’ to execute only every 20
triggers, you would send ALG:SCAN:RATIO ’ALG3’,20, followed by an
ALG:UPDATE command. ’ALG3’ would then execute on the first trigger
after INIT, then the 21st, then the 41st, etc. This can be useful to adjust the
Summary of Contents for VXI 75000 C Series
Page 2: ......
Page 16: ...16 ...
Page 18: ......
Page 30: ...30 Getting Started Chapter 1 Notes ...
Page 32: ...32 Field Wiring Chapter 2 Figure 2 1 Channel Numbers at SCP Positions ...
Page 44: ...44 Field Wiring Chapter 2 Figure 2 11 HP E1415 Terminal Module ...
Page 54: ...54 Field Wiring Chapter 2 Notes ...
Page 61: ...Programming the HP E1415 for PID Control 61 Chapter 3 Programming Overview Diagram ...
Page 136: ...136 Creating and Running Custom Algorithms Chapter 4 Notes ...
Page 152: ...152 Algorithm Language Reference Chapter 5 Notes ...
Page 304: ...304 HP E1415 Command Reference Chapter 6 Command Quick Reference Notes ...
Page 308: ...308 Specifications Appendix A Thermocouple Type E 200 800C SCPs HP E1501 02 03 ...
Page 309: ...Specifications 309 Appendix A Thermocouple Type E 200 800C SCPs HP E1508 09 ...
Page 310: ...310 Specifications Appendix A Thermocouple Type E 0 800C SCPs HP E1501 02 03 ...
Page 311: ...Specifications 311 Appendix A Thermocouple Type E 0 800C SCPs HP E1509 09 ...
Page 312: ...312 Specifications Appendix A Thermocouple Type E Extended SCPs HP E1501 02 03 ...
Page 313: ...Specifications 313 Appendix A Thermocouple Type E Extended SCPs HP E1508 09 ...
Page 314: ...314 Specifications Appendix A Thermocouple Type J SCPs HP E1501 02 03 ...
Page 315: ...Specifications 315 Appendix A Thermocouple Type J SCPs HP E1508 09 ...
Page 316: ...316 Specifications Appendix A Thermocouple Type K SCPs HP E1501 02 03 ...
Page 317: ...Specifications 317 Appendix A Thermocouple Type R SCPs HP E1501 02 03 ...
Page 318: ...318 Specifications Appendix A Thermocouple Type R SCPs HP E1508 09 ...
Page 319: ...Specifications 319 Appendix A Thermocouple Type S SCPs HP E1501 02 03 ...
Page 320: ...320 Specifications Appendix A Thermocouple Type S SCPs HP E1508 09 ...
Page 321: ...Specifications 321 Appendix A Thermocouple Type T SCPs HP E1501 02 03 ...
Page 322: ...322 Specifications Appendix A Thermocouple Type T SCPs HP E1508 09 ...
Page 323: ...Specifications 323 Appendix A 5K Thermistor Reference SCPs HP E1501 02 03 ...
Page 324: ...324 Specifications Appendix A 5K Thermistor Reference SCPs HP E1508 09 ...
Page 325: ...Specifications 325 Appendix A RTD Reference SCPs HP E1501 02 03 ...
Page 326: ...326 Specifications Appendix A RTD SCPs HP E1501 02 03 ...
Page 327: ...Specifications 327 Appendix A RTD SCPs HP E1508 09 ...
Page 328: ...328 Specifications Appendix A 2250 Thermistor SCPs HP E1501 02 03 ...
Page 329: ...Specifications 329 Appendix A 2250 Thermistor SCPs HP E1508 09 ...
Page 330: ...330 Specifications Appendix A 5K Thermistor SCPs HP E1501 02 03 ...
Page 331: ...Specifications 331 Appendix A 5K Thermistor SCPs HP E1508 09 ...
Page 332: ...332 Specifications Appendix A 10K Thermistor SCPs HP E1501 02 03 ...
Page 333: ...Specifications 333 Appendix A 10K Thermistor SCPs HP E1508 09 ...
Page 334: ...334 Specifications Appendix A Notes ...
Page 346: ...346 Glossary Appendix C Notes ...
Page 388: ...388 Generating User Defined Functions Appendix F Notes ...