ABB LST400 - Venturi Flume

LST400 | ULTRASONIC LEVEL TRANSMITTER | OI/LST400-EN REV. E
22
100
90
80
70
60
50
40
30
20
10
0
0.00 2.46 4.92 7.38 9.84 12.30 14.76
LEVEL (FT)
PERCENTAGE (%)
PERCENTAGE VS. LEVEL
Level 13.94 ft
mA Output: 18.31mA
Instant: 2.46 ft
Temperature: 20°C
Percentage: 89.44%
Note: Due to the curve of the graph being non-linear all 21
points are needed from the lineariser.
The display shown to the bottom right is what LST400 will
display on the above application. The analogue output should
be approximately 18.31 mA.
Venturi flume
This is an example of a Venturi Flume application. The
transducer is mounted 3.94 ft / 1.20 m above the zero of the
flume, this is the Empty Distance. The Span is 1.97 ft / 0.60 m
and the Blanking Distance is 1.97 ft / 0.60 m. The transducer
must be fitted 3 x maximum head upstream. There is an
external counter connected to the relay counter. The water flow
must not dam up and cause a build-up inside the flume.
Flow
3.94 ft / 1.20 m
3 X H
Note: The Empty Distance is to the zero of the flume and not
the bottom of the flume.
Security code 
Mode FLOW
Empty distance 
Span 
Blanking 
Rate of change 
Fail timer 
Fail safe HOLD
Flow units Lt/sec
Maximum flow 
Flow curve Venturi
Setup relays YES
 Counter
 
 HI
 
 
Totaliser reset NO
Zero offset 