Installation & Operation Manual Proven Quality since 1892
ECON Limit Switch Box Fig. 79652 www.eriks.com
Rev.0 9
8.5 Setting of the Current Position Transmitter unit – CPT (Optional)
A potentiometer reads the current position of the actuator (valve) and transmits a resistance value to the
position transmitter PCB. The transmitter indicates the actuator (valve) position throughout the complete stroke and
converts resistance value it into a 4 to 20mA output signal.
Technical features
Power supply range :
12.5 to 37VDC (25V typical)
Current signal output:
4 to 20mA
Max. load resistance:
Max. resistance (Ohm) = (Supply voltage – 12.5) / 0.02
Potentiometer:
0 to 500Ω / 10kΩ
Operation temperature:
-20 to 60°C (-4°F to 140°F)
Dimension:
40 x 60 x 15mm
DC power supply
8.5.1 Calibration of the potentiometer
Operate the actuator into the closed position.
Connect an Ohm-meter to the P1 and P3 resistor. The value shall be approximately 1kΩ.
Loosen the potentiometer gear wheel from the shaft and connect the Ohm-meter to P1 and P3
and rotate the gear wheel gently until a value between 80 to 120Ω is achieved (100Ω preferred!).
While maintaining the value, tighten and lock the gear wheel to shaft.
8.5.2 Calibration of the zero span
The zero span setting has been calibrated by manufacturer. However, if re-calibration is required, please
follow the hereunder mentioned instruction:
Operate the actuator to the middle position and thereafter to the fully closed position.
As soon as the actuator reaches the fully closed position, adjust the “zero” rotary switch on the
PCB until a value of 20mA is achieved.
