Manual
4/4
Form 492 (11.13) ©SOR Inc. 
Calibration
14685 West 105th Street, Lenexa, KS 66215 
 913-888-2630 
 800-676-6794 USA 
 Fax 913-888-0767
Registered Quality System to ISO 9001
Printed in USA sorinc.com
Normal Calibration: Turn set point adjustment screw to move spring guide plate   
    into alignment with desired set point on calibration scale.
Precise Calibration: Device calibrated without reference to calibration scale 
    and low side vented. 
Test apparatus: Manometer
    Variable pressure source
    Test light or ohmmeter
 Connect variable pressure source to manometer and high side pressure port.
 Connect test light or ohmmeter to C-Common and NO - Normally Open switching 
 element contacts.
 Raise pressure and note manometer reading when circuit closes.
 Slowly drop pressure and note manometer reading when circuit opens.
 Use a screwdriver to turn set point adjusting screw: counterclockwise to increase set 
point, or clockwise to decrease set point.
 Repeat steps 3, 4 and 5 until contacts change at desired increasing or decreasing 
  differential pressure set point.
Do not remove other covers or attempt to adjust other parts of the 
mechanism. All have been precisely positioned at the factory and 
should not be moved in the  eld.




