Emerson 350 series Instruction Manual page 13

350 Actuator
Fault
1. Sluggish piston rod movement
or no piston rod movement
2. Unusual pump noises
3. Cycling operation
12
Table 9. Fault-Correction Guide
Possible Cause
Electrical system
a. Machine screw (key 123) not
removed
b. Reversed motor rotation
c. Input signal not reaching
actuator
d. Input signal not reaching coil
e. Coil shorted or dirty and does
not move with change in input
signal
Hydraulic system
a. Bypass valve not full closed
b. Pump relief valves improperly
adjusted
c. Nozzles improperly adjusted
d. Primary restrictions plugged
e. Seals leaking
2. Trapped air in suction side of
pump
CAUTION
Trapped air could damage
pump; shut off motor and
correct immediately.
3. If all other elements in the
system are functionally correct,
problem may be extreme pipeline
vibration.
Check
a. Remove cover (key 87) and
check to be sure screw has been
removed.
b. Check power connections on
motor and motor rotation arrow on
mounting bracket.
CAUTION
Improper rotation could
result in pump damage.
c. Check input signal wires at
terminal strip (key 90) to determine
if input signal is reaching actuator.
d. Check wires (keys 133, 128,
and 130) at terminal plug
(key 102), terminal strip (key 89,
figure 12), and at coil (key 37) to
determine if input signal is
reaching coil.
e. Check coil resistance with
ohmmeter (see table 2 for
approximate resistance of the
coils); inspect coil and magnet for
dirt.
a. Check bypass valve on side of
actuator.
b. Check per Checking and
Adjusting Pump Pressure section.
c. Check per Adjusting Nozzles
section.
d. –––
e. If pump is supplying fluid at
appropriate pressure and nozzles
are adjusted properly, seal may
require replacement.
2. Be certain filter (key 117) is
completely submerged in hydraulic
fluid; check all fittings to be sure all
are tight.
3. –––
Instruction Manual
Form 1387
June 2002
Correction
a. Remove screw and two locknuts.
b. Change motor power connections
if necessary.
c. If instrument supplying input
signal is functioning, correct the
input signal wiring.
d. Replace wires or terminals if
necessary.
e. Replace coil assembly if shorted;
clean coil and magnet per Cleaning
Force Motor section.
a. Close bypass valve by rotating
bypass valve stem (key 77,
figure 14).
b. Adjust per Checking and
Adjusting Pump Pressure section.
c. Adjust per Adjusting Nozzles
section.
d. Clean per Cleaning Primary
Restrictions section.
e. Replace per Replacing Seals
section.
2. Adjust position of filter by
loosening connection on pipe nipple
(key 283, not shown) at the pump,
re-positioning filter, and tightening
connection. Tighten all loose fittings.
3. Re-position actuator at 90
degrees to direction of pipeline
movement.