Spirax Sarco SP7-20, Инструкция по установке и обслуживанию

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IM-P706-03 CTLS Issue 1
17
SP7-20 Smart Positioner
(1) Increase linkage
(2) Decrease linkage
3.1.7 Positioner linkage
Fig. 9
The scale on the lever indicates the link points for the various stroke ranges of the valve.
Move the bolt with the follower pin in the oblong hole of the lever to adjust the stroke range of the valve to
the working range for the position sensor.
Moving the link point inwards increases the rotation angle of the sensor. Moving the link point outwards
reduces the rotation angle of the sensor.
Adjust the actuator stroke to make use of as large an angle of rotation as possible (symmetrical around the
center position) on the position sensor.
Recommended range for linear actuators: −28 to 28°
Minimum angle: 25°
Note: After mounting, check whether the positioner is operating within the measuring range.
3.1.8 Position of the actuator bolt
The actuator bolt for moving the potentiometer lever can be mounted permanently on the lever itself or on
the valve stem. Depending on the mounting method, when the valve moves the actuator bolt performs either
a circular or a linear movement with reference to the center of rotation of the potentiometer lever. Select
the chosen bolt position in the HMI menu in order to ensure optimum linearisation. The default setting is
actuator bolt on lever