Aalborg Vortex Insertion User Manual
Page 76
71
NO. INDICATION
LIKELY REASON
SOLUTION
4
There is no actual
fluid flow through
the Vortex meter
(no flow
conditions), but
LCD Display
reading some flow
rate.
Sensors wires are
disconnected from
CPU board.
Using ESD precautions and hazardous area
precautions, remove the electronics enclosure
window cover. Remove electronics assembly unit.
Disconnect the vortex sensor connector from the
CPU board (the CPU board is the board with LCD
display) via cut out in the terminal board.
Make sure two wires from the sensor are firmly
attached to outside pins of the connector and wire
from the center of the connector is attached to the
grounding terminal screw inside of the electronics
assembly enclosure.
Vortex flow meter
not properly
grounded.
Make sure flow meter enclosure case (external
Grounding terminal) is directly connected to earth
ground with minimal impedance (see pages110-113).
Flow Meter is too
sensitive to the
external noise or
vibration.
Using Key Pad, navigate to Submenu L1 “Diagnostic
Menu” and record following parameters: “FFT
Output”, “FFT Average”, “Sensors RMS” and consult
the factory with findings.
5
Erratic Flow rate
Reading
The flow rate may be
too low, just at the
cutoff of the meter
range, and the flow
cycles above and
below the cutoff
making an erratic
output.
The meter range is provided with product label
attached to the meter body (based on customer’s
application flowing conditions when the meter was
ordered). Consult the factory if necessary to
confirm the meter range based on current operating
conditions. It may be possible to lower the low flow
cutoff to increase the meter range.
Mechanical
installation may be
wrong.
Verify the straight run is adequate as described in
Paragraph 3.3 “PIPING GUIDELINES”. For in-line
meters, make sure the meter is not installed
backwards and there are no gaskets protruding into
the flow stream. For insertion meters, verify the
insertion depth and flow direction.
The meter may be
reacting to actual
changes in the flow
stream.
The displayed flow rate values can be smoothed
using the Flow damping and NRF time constant
parameters in the PWM DSP Menu (see paragraph
5.3.7.1).