Vega VEGAMET 381 Ex Instrucción De Servicio página 26

Setup with the integrated indicating and adjustment unit
which switching points the relays should switch on
and off again. Furthermore you have to distinguish
between the relay modes overfill and dry run
protection. You switch over by exchanging the ON/
OFF values of the relay.
Overfill protection: Relay is switched off
l
when the max. level is exceeded (safe
currentless condition), relay is switched on
again when the level falls below the min. level
(switch on point < switch off point)
Dry run protection: Relay is switched off
l
when the level falls below the min. level (safe
currentless condition), relay is switched on
again when the max. level is exceeded (switch
on point > switch off point)
à
To adjust the on and off switching points of
relay 1, set the function switch to position [1] or
[2], enter the switching points for ON or OFF
and save your settings. If necessary, proceed
in the same way with relay 2 (position [3] or
[4]).
1
o n
2
o f f
o n
3
o f f
Fig. 15: Relay modes
1 Filling height
2 Mode overfill protection
3 Mode dry run protection
Scaling
Scaling means the conversion of the measured
value into a certain parameter and unit. The
indication can then show e.g. instead of the
percentage value, the volume in liters. Indication
values of from -9999 to +9999 is possible.
26
off (on)
on (off)
t
L E D
à
First of all, determine the max. indicating range
and the number of decimal places after the
decimal point -- max. four decimal places can
be displayed. Select position [ 5 ] of the
function switch, place the decimal point in the
required position and save your settings.
à
Now select position [6] or [7] on the function
switch, enter the requested values for 100 % or
0 % and save your settings.
Damping
To suppress fluctuations in the measured value
display, e.g. caused by an agitated product sur-
face, an integration time can be set. This time can
be between 0 and 250 seconds. Remember that
the reaction time of the entire measurement will
then be longer and the sensor will react to
measured value changes with a delay. In general, a
period of a few seconds is sufficient to smooth the
measured value display.
à
Now select position [9] on the function switch,
enter the requested value and save your
settings
Current output 0/4 ... 20 mA
The characteristics of the current output can be
switched over from 4 ... 20 mA to 0 ... 20 mA.
à
Now select position [8] on the function switch,
adjust the requested characteristics curve and
save your settings
Simulation
To check if the settings ofVEGAMET 381 Ex are
correct, the simulation mode can be used. Any
individual measured value can be simulated and e.
g. the correct behaviour of the relays and the
connected instruments can be checked.
Switching over between the functions "OPERATE"
and "Simulation" is done by pushing the [+/-] keys
for at least 3 seconds. In the simulation mode, the
set value flashes on the display. The simulation can
be switched off by pushing both keys again for
approx. 3 seconds. If no key is pushed, the display
switches automatically over to "OPERATE" after
approx. 60 minutes and the simulation is termi-
nated.
VEGAMET 381 Ex