PARAMETER SETTINGS FOR POINT # 1
P001 Operation Enter "1" for
level
.
P002 Material Enter "2" for
solid
.
P003 Measurement Response Enter "1" for
slow
(0.1 m/min).
P004 Transducer Enter "107" for
XLT-30
.
P005 Units No entry required, (preset for
metres
).
P006 Empty Enter "30" for transducer face to Empty equals
30.00 metres
.
P007 Span No entry required, (preset to
29.01 metres
).
P070 Failsafe Timer Enter "2" for failsafe activation after
2 minutes
without a valid echo.
P071 Failsafe Material Level Enter "HI" for
advance to Span on "LOE"
.
P072 Failsafe Advance No entry required. (preset to
restricted
).
P100 Relay Set Up Enter "4" for
Hi, Lo, Hi Hi, and Lo Lo
alarm relays.
P101 Hi Alarm Enter "25" for Hi Alarm at
25.00 m
.
P102 Lo Alarm Enter "10" for Lo Alarm at
10.00 m
.
P103 Hi Hi Alarm Enter "27" for Hi Hi Alarm at
27.00 m
.
P104 Lo Lo Alarm Enter "5" for Lo Lo Alarm at
5.000 m
.
With process control equipment disabled, enter the RUN mode to monitor system performance and alarm
programming. Otherwise, perform a Reading Measurement simulation (P920).
When satisfied with system performance and programming:
» connect a high alarm indicator to Relay # 1 (see P100 = 4).
» connect a low alarm indicator to Relay # 2.
» connect a high high alarm indicator and filling equipment stop/start control to Relay # 3.
» connect a low low alarm indicator to Relay # 4.
(Note that relays are de-energized in "power off" and "alarm" conditions).
For cement applications (or any very dusty dry solids), measurement difficulties during vessel filling are
common. For this example (assume the maximum filling rate), failsafe operates as follows.
e.g. 09:15 am Echo lost at 6.00 m, low alarm is still on, failsafe countdown begins.
09:17 am Failsafe activated, actual level = 6.16 m, reported level = 6.00 m.
09:57 am Low alarm off, actual level = 9.36 m, reported level = 10.00 m.
12:27 pm High alarm on, actual level = 21.36 m, reported level = 25.00 m.
12:47 pm Infeed stopped, actual level = 22.96 m, reported level = 27.00 m.
When the dust settles (and the echo is regained) the reported level advances toward the actual
level. When the reported level reaches 25.55 m (5% of Span less than the high high alarm trip
point), the high high alarm goes off, restarting the infeed and filling the vessel to 27.00 m.
Material Volume
To perform a volume conversion for the preceding example, we’ll assume:
» the vessel is cylindrically shaped with a flat bottom.
» the vessel volume for Empty to 29.01 m (Span) is 1457 m
3
.
VOLUME PARAMETER SETTINGS
P050 Tank Shape Enter "1" for
vertical cylinder with flat bottom
.
P051 Max Volume Enter "1457" for
1457 m
3
.
Now in the RUN mode the Reading represents material volume in m
3
.
01/25/99
PL-508 82
To Next Page
Loading...
