Part 4 - trouble shooting – Dynasonics 901 Series Enhanced Ultrasonic Flow Meter User Manual
Page 30

Rev.
04/02
-29-
D901/M
PART 4 - TROUBLE SHOOTING
CONDITION
POSSIBLE CAUSE
Unit does not turn “ON” when power is
applied
• Check AC connections.
• Test the fuse
• Ensure the terminal block located in the
upper left corner of the main PCB is
secure
• Verify that ribbon cables between PCBs
are connected.
OVERRANGE light is ON
• Increase the value of the FULL SCALE
constant.
• Verify that fluid velocity is not greater
than 20 FPS [6.08 MPS]
FAULT light is ON; low SIGNAL
STRENGTH indication
• Ensure that the transducers are properly
mounted to the pipe.
• Verify that transducer connections are
correct
• Ensure that the pipe is full of moving
liquid.
• Increase SENSITIVITY so that right-
most SIGNAL STRENGTH light just
comes ON.
• On cleaner liquids, move the
transducers closer to a 90
o
pipe elbow.
• On dirtier liquids, mount the transducers
as described in CASE 3 of Part 2 of this
manual.
• If the pipe has a polyethylene liner,
move the transducers to another area.
The liner may contain an air void at this
location.
(continued)