2
ANTILOCK CONTROLLER
& RELAY
WS-20™SPEED SENSORS
EXCITERS
FRONT WHEEL REAR WHEELS
feature allows the WS-20™sensor to "self adjust" after it
has been installed in the mounting block and the wheel is
installed.
When the WS-20™sensor is inserted all the way into the
mounting block and the wheel is installed on the axle, the
hub exciter contacts the sensor, which pushes the sensor
back.Also,normalbearing play will "bump" thesensoraway
from the exciter. The combination of these two actions will
establisharunning clearance or air gap between the sensor
andexciter.
FIGURE 2 - SPEED SENSOR VOLTAGE CYCLE OUTPUT
PEAKTO PEAK
PEAKTO PEAK
HIGHSPEED
LOWSPEED
TECHNICAL INFORMATION
ElectricalConnector- 2 Pin.
OutputVoltage- With a 3,000 Ohm resistor across
thetwosensorleads,outputvoltage
measured on a VOM = .800 VAC
Minimum at 42 Hz, or
approximately5 mph.
SensorGap- 0 to .015 inch.
SensorBody- FormulatedEpoxy;.628" Diameter.
NormalResistance
RangeatRoomTemp- 2000-2500ohms
PREVENTIVE MAINTENANCE
1. Every 3 months; 25,000 miles; 900 operating hours; or
duringthevehiclechassis lubrication interval, makethe
visual inspections noted in "SERVICE CHECKS"
below.
2. Every12months;100,000miles;or3600operatinghours,
performtheOPERATIONALTESTinthis manual.
SERVICE CHECKS
Check all wiring and connectors. Make sure connections
arefreefromvisibledamage.
Examine the sensor. Make sure the sensor, mounting
bracket,andfoundationbrakecomponentsarenotdamaged.
Repair/replaceas necessary.
WARNING! PLEASE READ AND FOLLOW
THESE INSTRUCTIONS TO AVOID
PERSONAL INJURYOR DEATH:
When working on or around a vehicle, the following
general precautions should be observed at all times.
1. Park the vehicle on a level surface, apply the
parking brakes, and always block the wheels.
Always wear safety glasses.
2. Stop the engine and remove ignition key when
working under or around the vehicle. When
working in the engine compartment, the engine
should be shut off and the ignition key should be
removed. Where circumstances require that the
enginebe in operation, EXTREME CAUTION should
be used to prevent personal injury resulting from
contact with moving, rotating, leaking, heated or
electrically charged components.
3. Do not attempt to install, remove, disassemble or
assemble a component until you have read and
thoroughly understand the recommended
procedures. Useonlythepropertoolsandobserve
all precautions pertaining to use of those tools.
4. If the work is being performed on the vehicle’s air
brake system, or any auxiliary pressurized air
systems,make certain todrain the air pressurefrom
FIGURE 3 - TYPICAL ANTILOCK SYSTEM
