Linear Actuator Troubleshooting - Westerbeke 11.5KW-60Hz Service Manual

(
Problem
System appears dead.
(No actuator movement)
Engine runs, but at idle speed
Actuator
Actuator (removed)
Unit hunts during operation.
LINEAR ACTUATOR TROUBLESHOOTING
Tesl/Check
1. Check the battery voltage
at
the controller terminal block
with the Preheat switch depressed.
2. If there Is no signal or a weak signal from the
MPU. measure the AC voltage being produced by the
MPU while cranking the engine. Measure between the white
and black/wllite wire leads on the controller terminal strip.
While cranking the engine or
it
is funning at idle, the voltage
shoutd be 2.0-3.0 volts AC.
NOTE: The AC input fmpedance of meter must be
5000 ohms/volts or greater.
NOTE: When making this test in diesel units, disable the
preheat solenoid by disconnecting the
"s"
terminal connection
!lO
as not to damage the glow plugs.
3. Check the actuator with the Preheat switch depresssed
This provides DC voltage to the controller. Measure the
DC voltage between the actuator connections on the
controller block and the black DC
(~)
power connection
on the controller terminal block. Both connections should
have battery voltage +0.00 or -0.75 VDC.
a. Purple lead to Black DC (-).
b. Purple leadlpurple/white lead to Black DC (-).
NOTE: Continue this test (ONLY) if the battery
voltage is not present.
Co
The following checks are performed between the
connections at the actuator and the Black DC (~) connection
on the controller terminal block. This is to determine if there
is a break in the line between the controllers terminal block
connection and the actuator connections or the actuator
leads themselves.
1) Low voltage (t .0-2.0 VDC) at either actuator connections.
2) Battery voRage at both actuator connections.
3) Battery voltage at one actuator connection but
not at the second.
1. Check the controller by removing the two. purple leads
one at a time that come from the actuator off the controller
terminal block. Lift one actuator lead and depress the
preheat/on switch. Reconnect and do the same with the second.
a. Actuator does not retract (Diesel).
b. Shorted/open coil in actuator.
1. Improper governor adjustment.
2. Inadequate power supply voltage.
a. Connecta DC voltmeter to Red (+) and Black (-) leads
at the controller terminal block.
b. Disconnect both leads coming from actuator from
controller terminal block.
c. Connect one lead fram the actuator to the Red (+)
on the terminal block and the other actuator lead to
the Black (-)on the terminal block.
d. Momentarily energize the start switch. The actuator
Correct
l_lnspect the DC circuit back to the starting battery.
2. Check for damage to or improper adjusiment of
magnetic
pick~up.
replace or re-adjust.
3. Low voltage (1.0-2.0 VDC) at either actuator connections.
b. Replaee the controller if battery voltage is not present at
both the Purple leads.
1} Broken actuator lead, repair.
2) Broken actuator lead, repair or replace actuator:
3) Check actuator winding for open. Replace actuator.
1. Check for
a
shorted actuator lead. Replace the
. controller· because it should not cause the actuator
lever to go to full fuel when the engine is not running.
a. Replace controller.
b. Check resistance of actuator coil.
12 Volt 3.0 - 3.1 ohm
24 volt to.7 -10.8 ohm
1. Re-adJust the calibration.
2. If actuator doesn' fully retract
(then check the actuator leads.
If the voltage is less than. specified, check for
loose or poor connections
In
the DC circuit back to
the battery, check the K2 relay and its connections.
should fully retract as long as the switch is depressed.
Measure the DC voltageacross the Red (+) and Black (-lleads
while p':erforming this test. DC voltage must be greater han 80%
of the DC voltage measured across the battery supply.
9.0 VDC llJinimum
30.0 VDC maximum
NOTE: Reconnect the actuator leads properly after completing this test.
e. MPU positioned marginally too far away from flywheel e. Check the position of the MPU.
teeth giving erratic AC Input to controller.
I. Check resistance value 950 -1000 ohm
If problems continue to persist, contact your WESTERBEKE dealer for addllional assistance .
.....,. WESTERBEKE
Engines" Generatore
93