KROHNE SU 600 Ex EN - Manual (Page 17)

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3: Relay 2 switching point ON
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4: Relay 2 switching point OFF
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5: Decimal point position of the scaling
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6: Scaling for 100 %
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7: Scaling for 0 %
l 8: Switch over current output 0/4 … 20 mA
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9: Damping of the measured value (integration time)
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A: Offset correction
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B: Min. adjustment in % by modifying the level
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C: Max. adjustment in % by modifying the level
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D: Min. adjustment in mA without modifying the level
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E: Max. adjustment in mA without modifying the level
l F: No function
When a pressure transmitter is used, an offset correction
should be carried out first. These instruments are factory-set in
a certain position. If the pressure transmitter is now mounted in
a different position, its measuring range is shifted slightly. The
zero point is readjusted by carrying out the offset correction in
uncovered (unpressurised) condition. The complete measur-
ing range will be shifted by the deviating amount.
à
Make sure that the pressure transmitter is completely
unpressurised, uncovered (unimmersed) and mounted in
its final position.
à
Set the function switch to position [ A ]. The display
indicates now the actual sensor current in mA. Save the
current status by pushing the [ +/- ] keys simultaneously.
For this adjustment procedure, two sensor current values
(4 … 20 mA) must be entered corresponding to the levels 0 %
and 100 %.
When using a pressure transmitter, an offset correction should
be carried out to reach maximum accuracy. Carry out this
offset correction before adjustment and with the sensor
uncovered (unimmersed).
à
Select now position [D] or [E] on the function switch, enter
the current values in mA for min. or max. adjustment and
save your settings.
During this adjustment procedure, the current level is assigned
to a certain percentage value. For this reason, percentage
values that correspond to the actual filling levels must be
entered for the min. and max. adjustment. The ideal calibration
is at 0 % and 100 %. Because it is not always possible to
empty or fill a vessel completely, any value can of course be
Offset correction
Adjustment in mA without
changing the level
Adjustment in % by changing
the level
SU 600 Ex - 4 ... 20 mA signal conditioning 17
Setup with the integrated indicating and adjustment unit
30653
-EN
-050803