BENDIX TP-3DC TRACTOR PROTECTION VALVE Manual

Bendix ® TP-3DC
TRACTOR CONTROL
(PRIMARY) 3/8"-18 NPT
TRACTOR
CONTROL
(SECONDARY)
3/8"-18 NPT
STOP LIGHT
SWITCH
1/4"-18 NPT
TRACTOR SUPPLY
1/4"-18 NPT
™
FIGURE 1 - TP-3DC Tractor Protection VALVE WITH DOUBLE CHECK
DESCRIPTION
The tractor protection valve system protects tractor air
brakes during trailer breakaway and/or when severe air
leakage develops in the tractor or trailer. This function is
required by law.
In normal use the tractor protection valve is used to shut off
the trailer control line before disconnecting the tractor from
the trailer. It is usually mounted at the rear of the tractor
cab, and it is used in conjunction with a dash-mounted
control valve.
The TP-3DC ™ valve integrates tractor protection and double
check valve functions. It also has an integral single check
valve that prevents trapping of air in the trailer control line.
This prevents service and spring brake compounding, and
it avoids a trailer roll away situation if the trailer is parked
with the air applied.
A stoplight switch port allows direct stoplight installation,
and the auxiliary supply port, when connected to the
BP-R1 ™ control port, eliminates a tee in the tractor
supply line. Also, a QR-L
in the trailer control and/or supply port to meet timing
requirements.
™ Tractor Protection Valve with Double Check
DATE CODE
STAMPED HERE
AUXILIARY SUPPLY
1/4" -18 NPT
™
valve can be factory installed
LABEL WITH
TP-3DC VALVE
™
O.E. PC. NO. HERE
TRAILER CONTROL
1/2"-14 NPT
TRAILER CONTROL
1/2"-14 NPT
Port
Tractor Supply
Auxiliary Supply
Tractor Control (Primary)
Tractor Control (Secondary) TRAC CONT
Stop Light Switch
Trailer Supply
Trailer Control
Weight: 1.5 lbs.
Material: Die-cast aluminum
Operating pressure: 150 psi maximum
Operating temperature: -40° to 200° F
Figure 1 shows the TP-3DC
O.E. piece number, and date code identifi cations.
Figure 2 is a sectional view of the TP-3DC
Figure 3 presents the TP-3DC
system schematic.
1/2"-14 NPT
1/2"-14 NPT
QR-L ™ VALVE FACTORY
INSTALLED ON SOME
TP-3DC VALVE MODELS
™
Embossed I.D. Thread Size
TRAC SUP 1/4"-18 NPT
AUX SUP 1/4"-18 NPT
TRACT CONT 3/8"-18 NPT
3/8"-18 NPT
STP LT SW 1/4"-18 NPT
TRLR SUP 1/2"-14 NPT
TRLR CNTL 1/2"-14 NPT
™ valve with its port designations,
™ valve, and
™ valve in a partial air brake
1