Greyline TTFM 6.1, User Manual

Page: 56 / 79

Page 56
TTFM 6.1 Transit Time Flow Meter
Possible Causes:
Corrective Action:
NO ECHO INDICATION Icon: No Echo (cont.)
Empty pipe or partially filled

Pipe must be fluid filled and acoustically transparent in order to
obtain echoes.
Coupling compound washed out, or
sensor loose on pipe.

Remount sensor

Use Super Lube® Silicone Compound
SENSOR CONNECTIONS
OPEN/SHORT SENSOR ICON

No sensors attached

Short in transducer, or in triax transducer cable. Follow Sensor
Connections steps
Sensor Connections

Check sensor connections at TTFM and at sensor junction box.

Note: Refer to Sensor Cable Resistance Test to test final
connections.
METER READING HIGHER THAN EXPECTED?
Calibration Error

Review calibration menu. Pipe dimensions and fluid
selection/fluid velocity.
Higher flow rate than expected

Investigate pump/valves. Compare velocity with alternate
instrument.
Erratic measurement (set damping to
0% to check) due to electrical noise
or poor signal quality.

Ensure all Flowmeter wiring is in METAL conduit and sensor
shield is properly grounded.

Ensure correct power input Ground connection (<1 ohm
resistance).

Ensure 4-20mA Shield connected to Instrument Ground stud.

Contact Greyline for further assistance.
High viscosity fluid

Laminar flow profile due to high viscosity fluid requires an
adjustment to Cal Const.