Vega VEGAMET 861 - Page 27

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7 Set up with the integrated display and adjustment unit
VEGAMET 861 • 4 … 20 mA/HART
58866-EN-200401
mA for the empty vessel (0 %) (dry adjustment or adjustment without
medium).
Max. adjustment (full vessel)
If you want to use the currently measured level as a 100 %value,
select the menu item "Accept" (live adjustment or adjustment with
medium). If the adjustment is to be carried out independently of the
measured level, select the option "Edit". Now enter the appropriate
current in mA for the full vessel (100 %) (dry adjustment or adjustment
without medium).
Scaling means converting the measured value into a certain param-
eter and unit. The linearized percentage value is the source signal
which is used as basis for the scaling. The indication can then show
the volume in litres e.g., instead of the percentage value. Indication
values from max. -99999 to +99999 are possible.
A total of four relays is available. Relays 1 … 3 are freely available and
not yet assigned to a function. To be able to use these relays, they
mustrstbeactivated.Relay4isconguredinthefactoryasafail
saferelay,butcanalsobeconguredasadditionaloperatingrelay.
After activating a relay output, the desired mode of operation must
rstbeselected("Overllprotection/Dryrunprotection").
•
Overllprotection:Relayisswitchedowhenthemax.levelis
exceeded (safe currentless state), relay is switched on again when
thelevelfallsbelowthemin.level(switch-onpoint<switch-o
point)
•
Dry run protection:Relayisswitchedowhenthelevelfalls
below the min. level (safe currentless state), relay is switched on
again when the max. level is exceeded (switch-on point > switch-
opoint)
Additional modes such as "Pump control", "Switching window",
"Flow" and "Tendency" can be only set via PACTware/DTM or the
VEGA Tools app.
In the menu item "Reference value"itisdenedwhichmeasured
value serves as input signal for the relay (percentage/lin.-percent/
scaled).
EnterthevaluesforswitchingtherelayonandounderEnterthe
valuesforswitchingtherelayonandounder"Switching point".
The menu item "Behaviour in case of failure"deneshowtherelay
behaves if the assigned measuring point is disturbed. Here it can be
selected whether the switching state of the relay remains unchanged
orwhethertherelayisswitchedointheeventofafailure.
The current output is used to transfer the measured value to a super-
ordinate system, e.g. a PLC, a process control system or a measured
value indication. This is an active output, i.e. the current is provided
actively. The processing must hence have a passive current input. If
thecurrentoutputisnotused,itcanbedeactivatedintherstmenu
item.
Scaling
Outputs - Relay outputs
Outputs - Current output