User Manual

IOM-9540L10
C. Replacing The Amplifier: (See Figure 13)
1. Unhook the range spring (41) from the flapper
lever (38). (See Figure 11.)
2. Unscrew and remove the amplifier (53) sub-
assembly; the two amplifier mounting screws are
accessible from the rear of the positioner.
3. Install a new amplifier (53). Do not forget the
O-rings between the amplifier and the baseplate
(BP) (air baffle). Before tightening, carefully align
the mounting screws, position the amplifier (53) in
such a way that the flappers (52) are concentri-
cally aligned with the nozzles (51).
4. Hook the range spring (41) onto the flapper lever
(38).
5. Perform a maintenance basic adjustment and
recalibrate per Sections IV, V and VI.
VII. TROUBLE SHOOTING GUIDE
1. Actuator does not respond to applied input signal.
Possible Causes Remedies
A. Amplifier defective A1. Replace amplifier (See VI.C.).
B. Pneumatic connections reversed B1. Check connections.
C. Feedback lever not tightened C1. Screw feedback lever tight (See III.B.9.).
D. Stroke factor lever is loose on the shaft D1. Tight shaft.
E. Positioner mounted on the wrong side E1. Check mounting side in accordance with table in Section III.
F. Changeover plate in the wrong orientation F1. Check setting accordance with table in Section III.
2. Output pressure does not reach its maximum.
Possible Causes Remedies
A. Amplifier throttle dirty A1. Remove and clean throttle (See VI.B.).
B. Supply air too low B1. Check supply air pressure.
C. Flappers not parallel with nozzles C1. Align flappers (See VI.A.d.-f.).
D. Supply air filter dirty D1. Replace filter.
3. Actuator moves to end position.
Possible Causes Remedies
A. Positioner mounted on wrong side A1. Check mounting side in accordance with table in Section III.
B. Feedback lever not tightened B1. Tighten feedback lever.
C. Stroke factor lever loose on shaft C1. Tighten shaft (See Section III.B.).
Figure 13
SECTION VII