Field
Wiring
39
Preferred Measurement Connections
For any A/D Module to scan channels at high speeds, it must use a very short
sample period (<10
µ
second for the HP E1415). If significant normal mode
noise is presented to its inputs, that noise will be part of the measurement.
To make quiet, accurate measurements in electrically noisy environments,
use properly connected shielded wiring between the A/D and the device
under test. Figure 2-6 shows recommended connections for powered
transducers, thermocouples, and resistance transducers. (See Appendix E
page 361 for more information on Wiring Techniques).
Notes
1. Try to install Analog SCPs relative to Digital I/O as shown in
"Separating Digital and Analog Signals" in Appendix .
2. Use individually shielded, twisted-pair wiring for each channel.
3. Connect the shield of each wiring pair to the corresponding Guard
(G) terminal on the Terminal Module (see Figure 2-7 for schematic of
Guard to Ground circuitry on the Terminal Module).
4. The Terminal Module is shipped with the Ground-Guard
(GND-GRD) shorting jumper installed for each channel. These may
be left installed or removed (see Figure 2-8 to remove the jumper),
dependent on the following conditions:
a. Grounded Transducer with shield connected to ground at the
transducer: Low frequency ground loops (DC and/or 50/60Hz)
can result if the shield is also grounded at the Terminal Module
end. To prevent this, remove the GND-GRD jumper for that
channel (Figure 2-6 A/C).
b. Floating Transducer with shield connected to the transducer
at the source: In this case, the best performance will most likely
be achieved by leaving the GND-GRD jumper in place (Figure 2-6
B/D).
3. In general, the GND-GRD jumper can be left in place unless it is
necessary to remove to break low frequency (below 1 kHz) ground
loops.
4. Use good quality foil or braided shield signal cable.
5. Route signal leads as far as possible from the sources of greatest
noise.
6. In general, don’t connect Hi or Lo to Guard or Ground at the
HP E1415.
7. It is best if there is a D.C. path somewhere in the system from Hi or
Lo to Guard/Ground.
8. The impedance from Hi to Guard/Ground should be the same as from
Lo to Guard/Ground (balanced).
9. Since each system is different, don’t be afraid to experiment using the
suggestions presented here until you find an acceptable noise level.
IMPORTANT!
Содержание VXI 75000 C Series
Страница 2: ......
Страница 16: ...16 ...
Страница 18: ......
Страница 30: ...30 Getting Started Chapter 1 Notes ...
Страница 32: ...32 Field Wiring Chapter 2 Figure 2 1 Channel Numbers at SCP Positions ...
Страница 44: ...44 Field Wiring Chapter 2 Figure 2 11 HP E1415 Terminal Module ...
Страница 54: ...54 Field Wiring Chapter 2 Notes ...
Страница 61: ...Programming the HP E1415 for PID Control 61 Chapter 3 Programming Overview Diagram ...
Страница 124: ...124 Creating and Running Custom Algorithms Chapter 4 Figure 4 2 Algorithm Operating Sequence Diagram ...
Страница 136: ...136 Creating and Running Custom Algorithms Chapter 4 Notes ...
Страница 152: ...152 Algorithm Language Reference Chapter 5 Notes ...
Страница 304: ...304 HP E1415 Command Reference Chapter 6 Command Quick Reference Notes ...
Страница 308: ...308 Specifications Appendix A Thermocouple Type E 200 800C SCPs HP E1501 02 03 ...
Страница 309: ...Specifications 309 Appendix A Thermocouple Type E 200 800C SCPs HP E1508 09 ...
Страница 310: ...310 Specifications Appendix A Thermocouple Type E 0 800C SCPs HP E1501 02 03 ...
Страница 311: ...Specifications 311 Appendix A Thermocouple Type E 0 800C SCPs HP E1509 09 ...
Страница 312: ...312 Specifications Appendix A Thermocouple Type E Extended SCPs HP E1501 02 03 ...
Страница 313: ...Specifications 313 Appendix A Thermocouple Type E Extended SCPs HP E1508 09 ...
Страница 314: ...314 Specifications Appendix A Thermocouple Type J SCPs HP E1501 02 03 ...
Страница 315: ...Specifications 315 Appendix A Thermocouple Type J SCPs HP E1508 09 ...
Страница 316: ...316 Specifications Appendix A Thermocouple Type K SCPs HP E1501 02 03 ...
Страница 317: ...Specifications 317 Appendix A Thermocouple Type R SCPs HP E1501 02 03 ...
Страница 318: ...318 Specifications Appendix A Thermocouple Type R SCPs HP E1508 09 ...
Страница 319: ...Specifications 319 Appendix A Thermocouple Type S SCPs HP E1501 02 03 ...
Страница 320: ...320 Specifications Appendix A Thermocouple Type S SCPs HP E1508 09 ...
Страница 321: ...Specifications 321 Appendix A Thermocouple Type T SCPs HP E1501 02 03 ...
Страница 322: ...322 Specifications Appendix A Thermocouple Type T SCPs HP E1508 09 ...
Страница 323: ...Specifications 323 Appendix A 5K Thermistor Reference SCPs HP E1501 02 03 ...
Страница 324: ...324 Specifications Appendix A 5K Thermistor Reference SCPs HP E1508 09 ...
Страница 325: ...Specifications 325 Appendix A RTD Reference SCPs HP E1501 02 03 ...
Страница 326: ...326 Specifications Appendix A RTD SCPs HP E1501 02 03 ...
Страница 327: ...Specifications 327 Appendix A RTD SCPs HP E1508 09 ...
Страница 328: ...328 Specifications Appendix A 2250 Thermistor SCPs HP E1501 02 03 ...
Страница 329: ...Specifications 329 Appendix A 2250 Thermistor SCPs HP E1508 09 ...
Страница 330: ...330 Specifications Appendix A 5K Thermistor SCPs HP E1501 02 03 ...
Страница 331: ...Specifications 331 Appendix A 5K Thermistor SCPs HP E1508 09 ...
Страница 332: ...332 Specifications Appendix A 10K Thermistor SCPs HP E1501 02 03 ...
Страница 333: ...Specifications 333 Appendix A 10K Thermistor SCPs HP E1508 09 ...
Страница 334: ...334 Specifications Appendix A Notes ...
Страница 346: ...346 Glossary Appendix C Notes ...
Страница 388: ...388 Generating User Defined Functions Appendix F Notes ...
Страница 438: ...438 Index Writing the algorithm 129 values to CVT elements 120 values to the FIFO 121 Z ZERO CALibration ZERO 194 ...