User Manual

IOM-9540L

4. Unstable behavior; non-steady state in control loop.

Possible Causes Remedies

A. Amplification too high A1. Reduce amplification.

B. Gland friction on the valve too high B1. Loosen gland packing somewhat or replace.

5. Stroke range cannot be adjusted.

Possible Causes Remedies

A. Wrong range spring A1. Replace range spring (See Section IV.D.).

B. Positioner does not completely reduce B1. Check supply air pressure.

pressure B2. Check amplification.

B3. Adjust clearance between nozzle and flapper.

6. Positioner makes “buzzing” noise

Possible Causes Remedies

A. Wrong action setting A1. Check position of the bypass switch and the action.

Change as required.

REPAIR PARTS KITS

KIT A: Includes gaskets, O-rings and small parts. Order P/N 295-08-5-07410-00.

KIT B: Replacement pneumatic amplifier. Order P/N 653-75-5-09542-00.