VEGA Conductive electrodes - Manual (Page 35)

Conductive measuring system 35
Set-up VEGATOR 631 Ex
Pump control (Min-Max), mode A
Overflow protection
Pre-requirements
- First of all connect only the mass and max.
electrodes to the signal conditioning
instrument (terminal 1 and 3)
- Set the selection switch (13) to mode A
- Connect the signal conditioning instrument
to voltage supply
- Turn the potentiometer (2) to position 0
Adjust switch point
- Fill the vessel until the max. electrode is
covered approx. 1 cm
- Turn the potentiometer (2) slowly clockwise
until the yellow LED extinguishes
- Now connect the min. electrode to terminal
2 of the signal conditioning instrument.
The pump control is adapted to the product
conductivity, i.e. the relay deenergizes at
max. level and the transistor blocks.
This switching condition remains until the level
decreases the position of the min. electrode,
i.e. the relay energizes at min. level and the
transistor is conductive.
Only at max.-level the relay deenergizes
again and the transistor blocks.
Pump control (Min-Max), mode B
Dry run protection
Pre-requirements
- First of all connect only the mass and max.
electrodes to the signal conditioning
instrument (terminal 1 and 3)
- Set the selection switch (13) to mode B
- Connect the signal conditioning instrument
to power supply
- Turn the potentiometer (2) to position 10
Adjust switch point
- Fill the vessel until the max. electrode is
covered by approx. 1 cm
- Turn the potentiometer (2) slowly
anticlockwise until the yellow LED
extinguishes
- Now connect the min. electrode to terminal
2 of the signal conditioning instrument
The pump control is adapted to the product
conductivity, i.e. the relay energizes at max.
level and the transistor is conductive.
This switching condition remains until the level
has decreased the position of the min.
electrode, i.e. the relay deenergizes at min.
level and the transistor blocks.
Only at max. level the relay energizes again
and the transistor is conductive.
Note
For all switch point adjustments it must be
generally noted that between reaching of the
switch point and triggering of the switching
function an integration time of 0,5 s is
effective. The potentiometer must therefore
be turned slowly.
A probable additional integration time should
only be switched after the adjustment.
In all applications in conjunction with an inte-
gral resistor of 220 kOhm a line monitoring of
the mass and the max. electrode is ensured.