Possible Causes: Corrective Action:
METER READING ERRATIC
Sensor mounted too close to valve, pump or
elbow
•
Change sensor placement. Recommended 6-10
diameters from elbows, and 30 diameters from
pumps, controlling valves, orifice plates,
nozzles or open pipe discharge
NO FLOW INDICATION
Not enough suspended particles or gases in the
fluid
•
Relocate sensor in more turbulent pipe section.
Mount sensor at 12 o'clock position on
horizontal pipe
Coupling compound washed out, or sensor loose
on pipe
• Remount sensor
• Use Dow Corning Silicone #4
Power interruption. No flow. • Check fuse/breaker. Confirm flow
METER READING TOO HIGH
Calibration error • Review
UNITS/MODE menu and Pipe ID
Vibration or noise on the pipeline
•
Install in another location.
Pipe is not full
•
Remount Sensor on vertical pipe
Nearby velocity increasing device (pump, valve,
orifice plate)
•
Relocate sensor >30 pipe diameters from
velocity increasing device
Local electrical noise
•
Ensure all Flowmeter wiring is in METAL
conduit and sensor cable shield is connected to
Ground stud
Variable Speed Drive interference
•
Follow Drive manufacturers wiring and
Grounding instructions
•
Relocate Flowmeter electronics, Sensor and
wiring away from VSD
Page 22
DFM 5.0 Doppler Flow Meter
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