Emerson Model 1700 用户手册

Refer to the sensor and transmitter installation manuals for grounding requirements and
instructions.

A loop test is a way to verify that the transmitter and the remote device are
communicating properly. A loop test also helps you know whether you need to trim mA
outputs.

10.12.1

Perform loop tests using the display (standard option)

A loop test is a way to verify that the transmitter and the remote device are
communicating properly. A loop test also helps you know whether you need to trim mA
outputs.

Before performing a loop test, configure the channels for the transmitter inputs and
outputs that will be used in your application.

Follow appropriate procedures to ensure that loop testing will not interfere with existing
measurement and control loops.

1.

Test the mA output(s).

a. Choose and select a low value, e.g., 4 mA.

Dots traverse the display while the output is fixed.

b. Read the mA current at the receiving device and compare it to the transmitter

output.

The readings do not need to match exactly. If the values are slightly different,
you can correct the discrepancy by trimming the output.

c. At the transmitter, activate Select.
d. Scroll to and select a high value, e.g., 20 mA.

Dots traverse the display while the output is fixed.

e. Read the mA current at the receiving device and compare it to the transmitter

output.

The readings do not need to match exactly. If the values are slightly different,
you can correct the discrepancy by trimming the output.

f. At the transmitter, activate Select.

Troubleshooting

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