Programming the HP E1415 for PID Control
77
Defining Standard PID Algorithms
The HP E1415 provides you the choice of two different pre-defined PID
algorithms that are widely used in process control.
The Pre-defined
PIDA Algorithm
Figure 3-5 shows the block diagram of the PID algorithm that is defined
when you execute
ALG:DEFINE ’ALGn’,’PIDA(<inp_channel>,<outp_channel>)’
PIDA algorithm implements the classic PID controller. This implementation
was designed to be fast. In order to be fast, this algorithm provides no
clipping limit, alarm limits, status management, or CVT/FIFO
communication (History Modes). The algorithm performs the following
calculations each time it is executed:
Error = Setpoint - <
inp_chan
>
I_out = I_out + I_factor * Error
<
outp_chan
> = P_factor * Error + I_out + D_factor * (Error - Error_old)
Error_old = Error
See the program listing for PIDA in Appendix D page 347.
The Pre-defined
PIDB Algorithm
Figure 3-6 shows the block diagram of a more advanced algorithm that is
favored in process control because of the flexibility allowed by its two
differential terms. The "D" differential term is driven by changes in the
process input measurement. The "SD" differential term is driven by changes
in the setpoint variable value. You can define this algorithm by executing the
command ALG:DEFINE ’ALGn’,’PIDB(<inp_channel>,
<outp_channel>,<alarm_chan>)’
Setpoint
Variable
+
+
+
+
-
<outp_chan>
channel
<inp_chan>
channel
process
P_factor
Variable
D_factor
Variable
I_factor
Variable
Σ
Σ
I_out
variable
Error
variable
Figure 3-5. The Simple PID lAlgorithm "PIDA"
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 ...