Instruction Manual
D200158X012
4194S Controllers
July 2018
46
Pivot Assembly A (Key 114)
CAUTION
Avoid bending or kinking the drive flexure during the following procedure. Bending or kinking the drive flexure can result
in product damage, as well as impaired performance.
1. Decrease the remote set point pressure to 0 psig.
2. Remove the tie bar (key 106).
3. Note where link A (key 116) is connected. Disconnect the link from the lever arm on the pivot assembly.
4. Disconnect the drive flexure (key 79) from the adjustment arm of the pivot assembly. Be careful not to bend or kink
the drive flexure.
5. Remove the screw (keys 122), the washer (key 123) and the nut (key 124) that attach the guide flexure to the top of
the pivot assembly.
6. Remove the pivot screw and spring washer (keys 109 and 112) and the mounting screw (key 102) attaching the
pivot assembly to the mounting plate. Lift out the pivot assembly.
7. Loosen the screw (key 118) on the adjustment arm of the replacement pivot assembly, and set the arm to the same
length as the arm on the pivot assembly being replaced. Tighten the screw.
8. To replace the pivot assembly, first put the spring washer on the screw. Then, install the screw through the pivot
assembly into the mounting plate.
9. Connect the guide flexure to the top of the new pivot assembly with the screw (key 122), the washer, and the nut as
it was before.
10. Increase the remote set point pressure to 50 percent of input span.
11. Connect the drive flexure to the arm on the new pivot assembly, making sure it stays straight and horizontal. Before
tightening down the drive flexure, set the pivot in the middle of the bushing end play. Tighten down the drive
flexure to hold the pivot in that position. Do not kink or twist the flexure when tightening the screws. Adjust the
length of the pivot arm if necessary until the flexure is straight.
12. Decrease the remote set point pressure to 0 psig.
13. Connect the end of link A (key 116) to the pivot lever arm in the same position noted in step 3.
14. Replace the tie bar (key 106).
15. Refer to the Maintenance Calibration procedure.
Pivot Assembly B (Key 115)
1. Refer to figure 5-3 for the key‐numbered assembly.
2. Decrease the remote set point pressure to 0 psig.
3. Note where the links are connected. Disconnect the links (keys 116 and 126) from the arms of pivot assembly
(key 115).
4. Remove the two screws (key 102) attaching the pivot assembly to the mounting plate (key 111). Remove the pivot
assembly.
5. Loosen the linearity adjustment screw on the replacement pivot assembly and set it in the same position as the
adjustment on the original pivot assembly. Tighten the screw.
6. Set the replacement pivot assembly on the mounting plate, and attach it with the two machine screws.
7. Attach the links (keys 116 and 126) to the arms of the new pivot assembly in step 3.
