Greyline Instruments PDFM 5.1, User Manual

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Page 19
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.