Instruction Manual
D200124X012
2500 and 2503 Controllers/Transmitters
June 2017
19
191 mm (7.5 inch) change at 1.7 bar (25 psig). Set the gap at a pressure low enough to be compatible with the limitations of the
diaphragm control valve or other final control element.
1. Turn on the supply pressure. If necessary, adjust the 67CFR regulator to produce the desired differential gap by
loosening the locknut (figure 9) and turning the adjusting screw clockwise to increase or counterclockwise to
decrease pressure. Tighten the locknut.
2. Locate the process variable at its minimum value.
Note
Adjustment of the RAISE LEVEL control can set the switching points anywhere within the length of the displacer. Be careful not to
set the switching points so that one is off the displacer.
3. Set the RAISE LEVEL control to 0 and then reset it as follows:
a. For direct‐acting controllers, set it between 1.0 and 1.5.
b. For reverse‐acting controllers, set it between 3.5 and 4.0.
4. The OUTPUT gauge should read 0 bar (0 psig) for direct or full supply pressure for reverse action.
5. Increase the process variable until the OUTPUT gauge changes to full supply pressure for direct or 0 bar (0 psig) for
reverse action. The process variable should be at the desired high trip value.
6. Decrease the process variable until the OUTPUT gauge changes to 0 bar (0 psig) for direct or full supply pressure for
reverse action. The process variable should be at the desired low trip value.
7. If all prestartup checks are satisfactory, proceed to the Startup section. If performance is unsatisfactory, proceed to
the Calibration section.
Adjustments
Control Action
The following is a definition of control action.
D
Direct Action
—Increasing fluid level, interface level, or density, increases the output signal.
D
Reverse Action
—Increasing fluid level, interface level, or density, decreases the output signal.
Controller/transmitters factory‐set for reverse‐acting have the suffix letter R added to their type number.
The control action is determined by the cage head mounting position and by the Bourdon tube‐flapper arrangement in
the controller/transmitter. Refer to figure 4 for mounting positions and to figure 15 for Bourdon tube‐flapper
arrangements. To change the action, refer to the changing action procedure in the Maintenance section.
Level Adjustment (Controllers Only)
To make a level adjustment, open the controller cover, loosen the knurled adjustment screw, and rotate the
adjustment lever around the RAISE LEVEL dial. To raise the fluid or interface level, or increase density, rotate this knob
