Power a HART transmitter
Figure 4-4:
The Trex unit measures both voltage and current from the HART + pwr terminals. An internal 167 Ohm
resistor is used when the Trex unit powers the device.
CAUTION!
Do not insert a resistor in parallel with either the HART + pwr or HART terminals on the Trex unit, or
in parallel with the device's communication terminals. This will interfere with the current
measurements and may prevent communication.
Measure voltage on an externally-powered HART transmitter
Figure 4-5:
A.
Voltage source
Loop Diagnostics application
User Guide
131
Summary of Contents for AMS Trex
Page 1: ...User Guide Rev 3 August 2017 AMS Trex Device Communicator User Guide ...
Page 8: ...Contents vi User Guide ...
Page 130: ...Field Communicator application 122 User Guide ...
Page 186: ...Fieldbus Diagnostics application 178 User Guide ...
Page 198: ...Technical specifications 190 User Guide ...
Page 206: ...Glossary 198 User Guide ...