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PDFM 5.1 Portable Doppler Flow Meter
Possible Causes: Corrective Action:
Coupling compound washed out, or sensor loose on
pipe
Remount sensor
Use Dow Corning Silicone #4
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
Variable Speed Drive interference
Follow Drive manufacturers wiring and
Grounding instructions
Relocate Flowmeter, Sensor and wiring away
from VSD
BATTERY CONDITIONING
To restore or condition your PDFM 5.1 battery
for best performance fully discharge the unit
(leave it on with backlight lit until it switches
off) and then charge for 6 hours, disconnect
charger momentarily, reconnect and charge
again for 6 hours.