Calibrating The Position Transmitter - Samson 3274 Mounting And Operating Instructions

Start-up

7.3 Calibrating the position transmitter

1. Set the slider switches SW3 and SW4 depending on the required position feedback sig-
nal (see Table 7-1):
SW3 and SW4 to ON: 4 to 20 mA/2 to 10 V
SW3 and SW4 to OFF: 0 to 20 mA/0 to 10 V
2. Connect an ammeter to terminals 31 (+) and 32 (–) or a voltmeter to terminals 32 (–) and
33 (+) (in this case, after jumpering the terminals 31 and 32).
3. Move the actuator stem to the lower end position (manually or by entering an input sig-
nal).
4. Position the segment gear S1 with the corresponding arrow tip depending on the valve
rated travel (15 or 30 mm) pointing towards the axis of the potentiometer P1.
S1
5. Hold the segment gear S1 and turn the axis of potentiometer P1 clockwise using a suit-
able screwdriver as far as it will go.
6. Turn axis of potentiometer P1 counterclockwise until the required value for the lower end
position is measured.
7. Move the actuator stem to the top end position (manually or by entering an input signal).
8. The value for the top end position should be indicated on the measuring instrument. It
can be adjusted with the 'Span out' adjuster.
Note
To reverse the characteristic, swap over the connecting wires (green and white) at the termi-
nals eL and aL.
7-6
Segment for 15 mm travel
Segment for 30 mm travel
Position of the arrow when the
actuator stem is fully extended
P1 P2
EB 8340 EN