User Manual for LEVIFLOW
®
LFSC-D Flowmeters
www.levitronix.com
PL-4507-00, Rev08, DCO# 20-024
27
5
Inspection and Maintenance
The
LEVIFLOW
®
ultrasonic flowmeters do not require special maintenance since there are no moving parts
that can be subjected to wear and tear. However, the following periodical checks are recommended to
ensure smooth and reliable operation:
1. Check for excessive mechanical stress onto the tubing clamped on the flow sensor body for example caused by
bended tubing.
2. Inspect for loosen connections caused by excessive vibrations.
3. Inspect the sensor visually for any deposits, excessive bubbles or foreign materials in the measuring tube.
4. When using the tubing for longer operation it is recommended to change the clamp-area on the tubing in order
to account for creeping affects in the clamp-area.
6
Troubleshooting
6.1 Common Troubles
#
Phenomenon
Possible Cause
Countermeasure
1
“0-Er” indication on converter display
Zero adjustment is not working
properly.
Check if the circuit is filled with liquid and that zero flow is
assured, and conduct zero adjustment again
2
“b-Er” indication on converter display
Incorrect signal received from
measurement in the sensor.
- Check if measuring tube is filled with liquid.
- Check if there is something in the measuring path
disturbing the ultrasonic wave (bubbles, particles etc).
- Check if excessive noise is generated in the vicinity of the
sensor (devices like motors, high voltage cables etc).
- Check if the cables are connected correctly and not
damaged.
3
“c-Er” indication on converter display
Parameter communication to
sensor is not working properly
or corrupt data on sensor.
- Check if sensor is connected.
- Check sensor cabling and connection.
- Disconnect and reconnect sensor.
4
Zero flow is indicated even if there is
flow in the hydraulic circuit
Wrong parameter and
mechanical setup of sensor or
zero adjustment performed
under flow conditions.
- Check if the parameters have been set correctly.
- Check if the flow direction is correct.
- Redo zeroing at 0 lpm.
5
Zero flow is indicated at flow level
below cut-off value.
Standard cut-off value as
shown in
is not
adequate for application.
- Adapt lower cut-off value with
LEVIFLOW
®
Service
Software
6
The flow indication does not match
the real flow
Wrong parameter settings,
excessive bubbles or solids in
the measurement path.
- Check if the parameters in the converter are set correctly.
- Inspect the flow path for stagnating solids.
- Inspect the measurement path for excessive bubbles.
7
Above full scale flow is indicated or
the flow signal is unstable
Wrong parameter settings,
excessive bubbles or solids in
the measurement path.
- Check if the parameters in the converter are set correctly.
- Inspect the flow path for stagnating solids-
- Inspect the measurement path for excessive bubbles.
8
Spikes on flow measurement
Influence from other devices.
- Use the standard EMI ferrites on the sensor cables.
Table 14: Potential troubles and the possible countermeasures
6.2 Troubleshooting with Levitronix
®
Service Software
For debugging, data collection and configuration of the flowmeter system the
Levitronix
®
Service Software
is
available at
Levitronix
®
. Contact
Levitronix
®
for a sample of the service software and the according manual
(see reference on title page of this manual)
.
An approved USB to RS485 adaptor with the according
connection cable can be ordered according to the information in
