14.2 Setting of 4-wire system 4 – 20 mA
.
Connect voltage for electronic position transmitter.
.
Move valve to end position CLOSED.
.
Take off cover at switch compartment.
.
Pull off indicator disc.
.
Connect ammeter for 0 – 20 mA to measuring points (MP1/
MP2) (figure J).
The circuit (external load) must be connected (observe
max. ext. load R
B
), or the appropriate poles at the AUMA
plug/ socket connector must be linked (refer to terminal
plan), otherwise no value can be measured.
.
Turn potentiometer (R, figure H) counter-clockwise until stop is felt.
.
Turn potentiometer (R) slightly back from the stop.
.
Turn trimmer potentiometer (R6 - “0", figure J) clockwise until output cur-
rent starts to increase.
.
Turn back potentiometer (R6 - “0") until a residual current of approx.
0.1 mA is reached.
.
Move valve to end position OPEN.
.
Set trimmer potentiometer (R5 - “max.”) to end value 16 mA.
.
Move valve to end position CLOSED.
.
Set potentiometer (R5 - “max.”) from 0.1 mA to initial value 4 mA.
This results in a simultaneous shift of the end value by 4 mA, so that the
range is now 4 – 20 mA.
.
Approach both end positions anew and check setting. If necessary, correct
the setting.
.
Press indicator disc on shaft and perform setting as described on page
12, clause 9.
.
Clean sealing faces at cover and housing; check whether O-ring is in good
condition. Apply a thin film of non-acidic grease to the sealing faces.
.
Replace cover on switch compartment and fasten bolts evenly crosswise.
15
Part-turn actuators SG 03.3 – SG 04.3
Operation instructions
AUMA NORM
