Bendix Commercial Vehicle Systems ATR-1 ANTILOCK TRACTION RELAY 02/11 - Manual

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SD-13-481
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DESCRIPTION
The ATR-1 ™ antilock traction relay valve is a specialized air
brake valve developed for use on Bendix antilock/traction
equipped vehicles.
It is essentially three separate valves working in
combination in a single housing. An R-14
® style service
relay is the base valve and is fi tted with a modifi ed cover
containing a double check valve and a traction control
solenoid. The ATR-1
™ valve contains both air and electric
components to provide the service braking and traction
control (differential braking) functions. A Bendix antilock
traction controller can be mounted to the ATR-1
™ valve or
a cover plate can be installed and the antilock controller
mounted elsewhere on the vehicle. When an ATR-1
™ valve
is combined with an antilock traction controller the resulting
assembly is referred to as an antilock traction assembly.
The ATR-1 ™ valve replaces the standard relay valve used
to control the rear axle service brakes and performs the
standard relay function. Like the standard relay valve
it replaces, the ATR-1
™ valve (sometimes with attached
antilock controller) is normally mounted near the service
brakes it serves. A mounting bracket, furnished with the
valve, permits either frame or cross member mounting.
All air connections on the ATR-1
™ valve are identifi ed for
ease of installation. The letter identifi cation and air line
connections are shown below for reference.
ATR-1 ™ VALVE AIR CONNECTION
EMBOSSED
IDENT.
Supply (to reservoir) SUP
Delivery (to brake chamber) DEL
Service (to brake valve rear delivery) SER
Control (not drilled or threaded on
ATR-1
™ valve)
CON
The ATR-1 ™ valve is part of the R-12 ® family of relay valves
which includes the R-12 ® , R-14 ® , BP-R1 ® , AR-1 ™ .
The internal components of the relay portion of all of these
valves are interchangeable with the R-12
® valve and
therefore the same basic components are used to service
all of them. The ATR-1
™ valve is available with various
crack pressures to accommodate specifi c applications,
however, the standard is 4 psi.
Bendix ® ATR-1 ™ AntiLock Traction Relay Valve
SUPPLY
PORT
BODY
MOUNTING
BRACKET
SERVICE
PORT
CONTROLLER MOUNTING
HOLES (4)
UNTAPPED PORTS COVER PLATE FOR
REMOTE MOUNT
REMOTE MOUNT
ATR-1
™ RELAY
VALVE
ALTERNATE
CASTING ON
NEWER VALVES
(NOTE THAT THE
SERVICE PORT
LOCATION IS
CHANGED)
UNDRILLED
“CON” PORT
DELIVERY
PORTS (4)
2 PIN SOLENOID
CONNECTOR
SUPPLY
PORT
FIGURE 1 - ATR-1 ™ ANTILOCK TRACTION RELAY VALVE
TRACTION
CONTROL
SOLENOID
SERVICE
PORT