2. Unplug the terminal blocks from the terminal board on the core processor.
3. Using a digital multimeter (DMM), check the pickoff coils by placing the DMM leads on the unplugged
terminal blocks for each terminal pair. See Table 17-5 for a list of the coils. Record the values.
Table 17-5: Coils and test terminal pairs
Coil Sensor model Terminal colors
Drive coil All Brown to red
Left pickoff coil (LPO) All Green to white
Right pickoff coil (RPO) All Blue to gray
Resistance temperature detector
(RTD)
All Yellow to violet
Lead length compensator (LLC) All except T-Series 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 CMF400 fixed resistor applies only to certain specific 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.
Troubleshooting Configuration and Use Manual
March 2019 MMI-20025166
302 Micro Motion Model 5700 Transmitters with Configurable Outputs
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