User Manual for LEVIFLOW
®
LFSC-D Flowmeters
www.levitronix.com
PL-4507-00, Rev08, DCO# 20-024
20
3.3.3 Mechanical and Hydraulic Installation
1.
In order to mechanically fix the sensor body, 2 fixation threads on the backside of the sensor
housing can be used (see
2.
Assure that at the mounting location, the allowed ambient temperature range (
) is not
exceeded.
3.
Clamp the sensor to the tubing according to the procedure described in
Section 3.3.4
. Use only
tubing material for the specified calibration (see calibration sheet).
4.
The flow circuit should be filled completely with fluid. The converter DSP (Digital Signal Processor)
contains special algorithms, which increase the robustness of the measurement against bubbles.
However, assure that excessive bubbles are avoided in the circuit.
5.
Ideal mounting position for the flow sensor is a slight angle with upward flow direction to avoid the
stagnation of bubbles and particles in the measuring path of the tubing.
6.
An arrow mark on the flow sensor (see
) indicates the flow direction. Make sure that the
arrow corresponds to the direction of the flow in the hydraulic circuit.
7.
Avoid excessive vibrations such as in the vicinity of displacement pumps. Vibrations might
influence the flow measurement. If vibrations sources can not be avoided, acoustic decoupling
technics between flowmeter and vibration source shall be considered.
8.
The flowmeter measures flow velocity. In order to obtain fully developed flow pattern for accurate
velocity measurement, straight run of 30x tubing ID upstream and of 12x tubing ID downstream is
recommended (see
for ID specifications of the sensor models). If non-uniform turbulent
flow or swirl flow is expected, install longer upstream straight run and/or a flow-rectifier.
9.
To install on a tubing that has open end, the sensor should be mounted in lower position of the
pipeline.
10. The sensor should be mounted where pressure in the pipe is above the atmospheric pressure in
order to avoid bubble generation by cavitation effects.
11. Devices like valves are recommended to be installed downstream of the sensor in order to prevent
formation of bubbles in the liquid. An upstream valve may form bubbles reducing the intensity of
the ultrasound signal and interfering with measurement.
12. A bypass pipe run (including bypass valve and shutoff valve) may be used for easy zero
adjustment and maintenance.
13. Please confirm that the maximum pressure is below the maximum pressure of the flexible tubing
and the maximum pressure of the sensor specified in
14. After setup a
“Zeroing” is recommended. Assure that the sensor is filled completely with the
according fluid and is free of bubbles. Stable liquid properties should be assured by flushing the
circuit with the final liquid until temperature and viscosity becomes stable. After this, zero flow shall
be realized. Then
push the “ZERO ADJ” button on the converters for about 3 seconds. During
adjustment “0ADJ” appears on the converter display (about 2s with blinking). The duration of
zeroing is about 26-60 seconds.
15. If Re-Zeroing is regularly necessary, automation is possible over the digital input of the converter.
For the configuration of the digital input the
Levitronix
®
Service Software
is needed. Consult the
manual of the
service software for more detailed description.
16. In the following cases a re-zero is recommended:
a. 30 minutes after power-on of a cool converter and sensor
b. Change of fluid properties (temperature, viscosity, density)
c.
Change of chemistry
d. Clamp-on of the sensor to a new tubing
e. Change of the hydraulic circuit
