14.1 Setting of 2-wire system 4 – 20 mA and 4-wire system 0 – 20 mA
The 2-wire system cannot be used in combination with the intermediate
position detection (page 16).
.
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).
In end position CLOSED with 4-wire system the value after
setting must be 0 mA, for 2-wire system it must be 4 mA.
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) counter-clockwise until stop is felt.
.
Turn potentiometer (R) slightly back from the stop.
.
Turn trimmer potentiometer (R6 - “0") clockwise until output current starts
to increase.
.
Turn back trimmer potentiometer (R6 - “0") until a residual current of
approx. 0.1 mA (or 4.1 mA in case of 2-wire system) is reached. This
ensures that the signal remains above the dead and live zero point.
.
Move valve to end position OPEN.
.
Set to end value 20 mA with trimmer potentiometer (R5 - “max.”).
.
Approach end position CLOSED anew and check minimum value (0 mA or
4 mA). 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.
14
Part-turn actuators SG 03.3 – SG 04.3
AUMA NORM
Operation instructions
Figure H
R
Figure J
R6 “0”
MP1 (–)
R5 “max”
MP2 (+)
