P.
30
UFM-50 Doppler Flowmeter
Possible Causes:
Corrective Action:
Sensor and GND wires reversed or not properly
connected
Check Sensor connections
Improper AC power input Ground
Use direct connection with 12 AWG wire to
nearest Ground pole (<1 ohm resistance).
SENSOR CABLE RESISTANCE TEST
Unplug the green sensor terminal from the Doppler board and connect the sensor wires as shown. With a
multimeter, perform resistance checks for each set of wires. One single loose terminal may cause false
readings.
Test across shield and core of each wire: TMTR (black/white) and RCVR (black). Resistance should be
around 82.5K ohms for any cable length. High readings indicate an open circuit and low readings
indicate a short or partial short in the sensor cable.
