SAF-HOLLAND XL-AR363-02 EDL/ARF Feature - Manual (Page 7)

XL-AR363-02 Rev. D 7
OPERATION
continued
Purpose:
The ARF (Automatic Reset Feature) is designed to ensure that the
External Dock Lock (EDL) flipper plates will not be trapped down
(engaged position) while the trailer is in motion. This is accomplished
by the use of two additional system valves.
NOTE:
Refer to (FIGURE 13) for component locations in the
EDL/ARF system.
Function:
Because both vehicle motion and position of the flipper plates must be
monitored, two additional system valves are used along with the height
control valve. A pilot valve monitors emergency brake pressure to
determine if the vehicle is parked or in motion. An auto reset (sensor)
valve monitors the position of the flipper plates (up or down) on the
External Dock Lock (EDL).
2
4
5
FIGURE 13
EDL/ARF System
Piping Diagram
(Numbers correspond
to the Parts List below)
7 EDL Actuator
3
1
EDL Flipper Plate Rod Assembly
shown in engaged (down) position.
6
9
8
10
4 3 / 4 ˝± 1 / 8 ˝
(120.65±
3.18mm)
Must use
Nylok
1/4˝-20 nut
(2 places)
11 Linkage
Assembly
From emergency
brake line
IMPORTANT:
The sensor valve is not interchangeable with
the HCV.
Tab
Parts List
1. EDL Flipper Plate (Shown in the Engaged Position):
The flipper plates are activated by the vehicle’s emergency parking
brakes. When the parking brakes are engaged, the flipper plates
rotate down to the engaged position. When the parking brakes are
released, the flipper plates rotate up to the disengaged position.
2. Primary Height Control Valve (1/4˝ and 3/8˝ air lines):
The Primary Height Control Valve must always be properly
adjusted to suspension design ride height to assure proper air
suspension and EDL function. When the flipper plates are up, the
primary height control valve has full function.
3. Pilot Valve:
A pilot valve is used to monitor emergency brake
pressure to determine if the trailer is parked or in motion.
4. Auto Reset (Sensor) Valve:
An auto reset (sensor) valve is
used to monitor the position of the EDL flipper plates (either up
or down). (To distinguish between a sensor valve and an HCV, a
sticker is placed on the sensor valve.) When the flipper plates are
in the up position, the standard height control valve maintains the
predetermined ride height. The auto reset (sensor) valve arm
should only be in the “up” position when the flipper plate is
down, or “down” when the flipper plate is in the up position.
Anytime this valve is in the neutral position it will cause the air
system to malfunction.
5. One-Way Check Valve (1/4˝ and 3/8˝ air lines):
Installed
to the middle port of the sensor valve.
6. Pressure Protection Valve:
Air pressure protection valve
ensures that safe air brake pressure is always maintained (70
psig—4.8 bars) in the air reservoir.
7. EDL Actuator:
Push rod retracts (with emergency brakes on) to
pull flipper plates down (engaged).
8. Air Reservoir:
Main vehicle air supply.
9. Air Spring:
When the emergency brakes are released, air is
supplied to the air springs, raising the trailer above ride height.
This frees the trapped flipper plates on the trailing arm load pads.
The flipper plates will then rotate up and out of the way. The
rotation upward of the flipper plates, rotates the arm of the
sensor valve downward. This disengages the sensor valve and
allows the primary height control valve to control all air flow for
ride height.
10. Choke Valve:
Can be installed in either side of the air
supply line to the actuator. Purpose of choke valve is to slow
down flipper plate rotation.
11. Auto Reset (Sensor) Valve Linkage Assembly:
Predetermine length of 4 3/4˝±1/8˝ (120.65±3.18mm) ensures
proper function of system. Linkage fasteners must be assembled
as shown above.