Table 16-7: Coils and test terminal pairs
(continued)
Coil Sensor model Terminal colors
Lead length compensator (LLC) All except T-Series, F025, F050, F100
A or B, F300 and CMF400 (see note)
Yellow to orange
Composite RTD CMFS025-150 and T-Series Yellow to orange
Fixed resistor (see note) CMFS007, CMFS010, CMFS015,
CMF400, and F300
Yellow to orange
Note
The F300 and CMF400 fixed resistor applies only to certain specific F300 and CMF400 releases. Contact
customer support for more information.
There should be no open circuits, that is, no infinite resistance readings. The left pickoff and right
pickoff readings should be the same or very close (±5 Ω). If there are any unusual readings, repeat the
coil resistance tests at the sensor junction box to eliminate the possibility of faulty cable. The readings
for each coil pair should match at both ends.
4. Test the terminals in the sensor junction box for shorts to case.
a) Leave the terminal blocks disconnected.
b) Remove the lid of the junction box.
c) Testing one terminal at a time, place a DMM lead on the terminal and the other lead on the
sensor case.
With the DMM set to its highest range, there should be infinite resistance on each lead. If there is
any resistance at all, there is a short to case.
5. Test the resistance of junction box terminal pairs.
a) Test the brown terminal against all other terminals except the red one.
b) Test the red terminal against all other terminals except the brown one.
c) Test the green terminal against all other terminals except the white one.
d) Test the white terminal against all other terminals except the green one.
e) Test the blue terminal against all other terminals except the gray one.
f) Test the gray terminal against all other terminals except the blue one.
g) Test the orange terminal against all other terminals except the yellow and violet ones.
h) Test the yellow terminal against all other terminals except the orange and violet ones.
i) Test the violet terminal against all other terminals except the yellow and orange ones.
There should be infinite resistance for each pair. If there is any resistance at all, there is a short between
terminals.
Postrequisites
To return to normal operation:
1. Replace the lid on the sensor junction box.
Important
When reassembling the meter components, be sure to grease all O-rings.
Troubleshooting Configuration and Use Manual
May2024 MS-00809-0200-1600
220 Emerson.com
To Next Page
Loading...
