Siemens SITRANS LR 300, Инструкция по эксплуатации, Страница: 52 / 140

Page 50 SITRANS LR 300 – INSTRUCTION MANUAL 7ML19985CL02
mmmm
m
Applicat
ions
Application Example: Horizontal Tank with Volume
The application is to obtain a level measurement and corresponding 4-20 mA output
proportional to vessel volume in a chemical tank. The bottom of the antenna flange is
3.5m from the tank bottom. The empty level is 0m (bottom) and the full level (span) is 3.0m
from the bottom. The maximum rate of filling or emptying is about 0.1 m/min. In the event
of a loss of echo, the SITRANS LR 300 is to go into Fail-Safe Hi after 2 minutes.
Run : To start normal operation, press the PROGRAM key .
Parameter Enter
P999 ---- master reset
P001 1 mode of measurement = level
P002 1 material = liquid
P003 2 measurement response = 1m/minute
P004 240 antenna = factory
P005 1 units = meters
P006 3.5 empty distance = 3.5m
P007 3 span = 3m
P050 7 tank shape = parabolic ends
P051 8000 maximum volume = litres
P052 .8 tank dimension A = 0.8 meters
P053 6 tank dimension L = 6 meters
P070 2 Fail-Safe timer = 2 minutes
P071 1 Fail-Safe = Hi
P820 12 algorithm = First echo
P837/838
(Note above) 2 & 1 Auto False Echo Suppression
Notes:
• The minimum distance from the flange face to the target is limited by near-blanking
P800.
• Only set P837 if the product is at least 2m (78”) away from the flange face. If it is
closer, leave P837 at 1 until the level drops and the distance increases beyond
2m (78”).
Calculate
actual volume
(e.g. 8000 litres
capacity)
3000mm
(122.4")
500mm
(20.4”)
A A L
SITRANS LR 300.book Page 50 Monday, June 10, 2002 7:18 PM