Positioner Action Change (4700P/4800P Only); From Air To Open / Direct To Air To Open/Reverse; From Air To Open / Reverse To Air To Open/Direct; From Air To Close / Direct To Air To Close/Reverse - GE Masoneilan 4700P Maintenance Manual

Positioner Action Change (4700P/4800P Only)

Whenever it becomes necessary to change positioner action from direct to reverse or vice versa,
it is important to be familiar with the following steps.
To remove or install the cam safely, the valve position must correspond to the low signal line on
lobe.
The positioner supply line, the vent and the lever S/A must be reversed.

From Air to Open / Direct to Air to Open/Reverse

1. Perform Steps 1 and 2 from "Cam Lobe Change" on page 49 for Air to Open/Direct
Acting Positioner. Cam is now removed.
2. Proceed to Field Mounting and Calibration section for Air to Open/Reverse Acting
Positioner and proceed as stated.

From Air to Open / Reverse to Air to Open/Direct

1. Perform Steps 1, 2 and 3 from "Cam Lobe Change" on page 49 for Air to Open/
Reverse Positioner. Cam is now removed.
2. Slowly reduce pressure applied to actuator to zero. (If handwheel was used to
place valve in open position back it off completely.) Valve is now closed. Remove
independent regulated air line from actuator.
3. Proceed to Field Mounting and Calibration section for Air to Open/Direct Acting
Positioner and proceed as stated.

From Air to Close / Direct to Air to Close/Reverse

1. Perform Steps 1 and 2 from "Cam Lobe Change" on page 49 for Air to Close/Direct
Acting Positioner. Cam is now removed.
2. Proceed to Field Mounting and Calibration section for Air to Close/Reverse Acting
Positioner and proceed as stated.

From Air to Close / Reverse to Air to Close/Direct

1. Perform Steps 1, 2 and 3 from "Cam Lobe Change" on page 49 for Air to Close/
Reverse Acting Positioner. Cam is now removed.
2. Slowly reduce pressure applied to actuator to zero. (If handwheel was used to
place valve in closed position back it off completely.) Valve is now open. Remove
independent regulated air line from actuator.
3. Proceed to Field Mounting and Calibration section for Air to Close/Direct Acting
Positioner and proceed as stated.
© 2015 General Electric Company. All rights reserved
.
Masoneilan 4700P/E & 4800P/E Positioners Manual =| 57