Flowserve L120-85 Actuator - Manual (Page 36)

Symptom Possible Cause Corrective Action
Unit operation is noisy 1. Inadequate lubrication (poor
quality or not enough)
1. nspect quality and quantity of lubrication in accordance with the Lubrica-
tion section. Add or replace lubricant as required.
2. Worn or damaged bearings 2. Disassemble unit and replace worn bearings, seals and lubricant.
Fuse blown 1. Incorrect fuse size 1. Verify fuses are sized correctly.
2. Pinched wire 2. Inspect control compartment to ensure Control Cover is not pinching or
making contact with wiring when installed.
3. Power surges 3. Investigate control circuit for surges.
Premature Torque Switch trip 1. Torque Switch setting too low 1. Increase Torque Switch setting as required up to, but not exceeding, the
maximum setting established by the Torque Switch Limiter Plate.
2. Valve packing too tight 2. Inspect valve packing for excessive tightness. Repair valve by replacing
packing as required. Refer to your valve manufacturer for specific instruc-
tions.
3. Unit is not properly aligned with
valve
3. Remove bolts between the unit and the valve and check for proper unit
alignment.
4. Valve needs lubrication 4. Check valve lubrication.
Torque Switch fails to stop actuator 1. Output rotation not in agreement
with unit wiring
1. Consult Limitorque to verify design rotation. If actual rotation is opposite
of design rotation, the Torque Switch needs to have contact wiring
reversed. See “Rewiring the Torque Switch for Non-Standard Drive Sleeve
Rotation.”
2. Low voltage supply to unit 2. Check incoming voltage supply.
Excessive current draw 1. Valve running loads higher than
expected
1. Inspect valve for possible causes of high running load. In particular,
check for excessive tightness of valve packing and for proper lubrication
of valve. Consult Limitorque for review of application.
Motor overload tripping 1. Excessive current draw 1. Inspect valve for possible causes of high running load. In particular,
check for excessive tightness of valve
packing and for proper lubrication of valve. Consult Limitorque for review
of application.
2. Incorrect overloads 2. Verify proper overloads selected for motor rating.
Excessive gear wear 1. Excessive loads 1. Verify actual loads are in accordance with both start and run capabilities
of your actuator.
2. Inadequate lubrication 2. Inspect quality and quantity of lubrication in accordance with the Lubrica-
tion section on pages 38–39. Add or replace lubricant as required.
3. Improper alignment 3. Inspect worn gears for evidence of uneven wear pattern.
4. Excessive operation (modulating
units)
4. Review number of starts. Repeated frequent repositioning (oscillation)
may indicate an unstable “loop” system. Review with Limitorque.
Excessive torque required to turn
Handwheel
1. Valve running loads higher than
expected
1. Inspect valve for possible causes of high running loads. In particular,
check for excessive tightness of valve packing, proper lubrication of valve
stem, bent or damaged valve, tight Stem/Torque Drive Nut fit, worn or
damaged Stem Nut.
2. Unit is not properly aligned with
valve
2. Take bolts off between the unit and the valve and check for proper unit
alignment.
Oil leaking from unit 1. Infrequent operation of actuator
resulting in grease separation
1. Institute periodic operation of unit into a maintenance program to keep
grease mixed. If not possible, schedule more frequent lubrication inspec-
tions to ensure adequate lubrication of gearbox.
2. Damaged or worn seals 2. Replace seals.
Limitorque L120-85 Installation, Operation and Maintenance FCD LMENIM1202-00 – 11/05