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6 - 2
Pressure Reducing Solenoid Valve
(machines without sequencing E.C.U.)
This valve controls the Safety Restraint Bar circuit, the door
latch circuit, brake circuit, and pressure reduction circuit.
It contains a reducing valve cartridge and a 3 position, 3 port
cartridge solenoid valve.
The relevant sections of the hydraulic and electrical circuits
are shown on the opposite page. Refer to the left hand
electrical schematic.
When first entering the machine the solenoid valve should be
in position
X
i.e. with the parking brake ON, the Safety
Restraint Bar in the access position (hence switch
19
open)
and the door open (switch
18
open). In this condition,
pressure from the auxiliary pump is dumped to the tank
(brake ON).
Closing the door correctly, moving the Safety Restraint Bar to
the operation position and starting the engine will energise
solenoid
16
and move the solenoid valve to position
Y
.
In this position the valve directs hydraulic power via the
loader joystick to the loader valve and other circuits, but the
brake pressure is still dumped to the tank.
Operation of the Parking Brake switch
15
energises solenoid
17
and de-energises solenoid
16
. This causes the solenoid
valve to move to position
Z
, directing hydraulic power via the
loader joystick as before, but also pressurising the brake
circuit (Brake OFF).
Key to L. H. Electrical Schematic
1
Reducing Valve Assembly
2
Reducing Valve
3
Solenoid Valve
4
Restrictor
14
Interlock Relay
15
Parking Brake Switch
16
Brake Solenoid
17
Operational Solenoid
18
Door Switch
19
Restraint Switch
29
Diode
78
Brake Switch Illumination
112
Fuse
Pressure Reducing Solenoid Valve
(machines with sequencing E.C.U.)
Note:
The sequencing E.C.U. was fitted to machines from
serial number 675358 but was not fitted to machines
manufactured after May 1996.
This valve controls the Safety Restraint Bar circuit, the door
latch circuit, brake circuit, and pressure reduction circuit.
It contains a reducing valve cartridge and a 3 position, 3 port
cartridge solenoid valve.
The sequencing E.C.U. inhibits the selection of the
operational and brake solenoids until firstly the door switch is
closed followed by the restraint switch. Unless the switches
are closed in the correct sequence the E.C.U. will not
operate.
The relevant sections of the hydraulic and electrical circuits
are shown on the opposite page. Refer to the right hand
electrical schematic.
When first entering the machine the solenoid valve should be
in position
X
i.e. with the parking brake ON, the Safety
Restraint Bar in the access position (hence switch
16
open)
and the door open (switch
17
open). In this condition,
pressure from the auxiliary pump is dumped to the tank
(brake ON).
Closing the door correctly and moving the Safety Restraint
Bar to the operation position triggers the sequencing E.C.U.
to close the interlock relay
11
. When the engine is started,
solenoid
14
is energised and the solenoid valve is moved to
position
Y
.
In this position the valve directs hydraulic power via the
loader joystick to the loader valve and other circuits, but the
brake pressure is still dumped to the tank.
Operation of the Parking Brake switch
12
energises solenoid
13
and de-energises solenoid
14
. This causes the solenoid
valve to move to position
Z
, directing hydraulic power via the
loader joystick as before, but also pressurising the brake
circuit (Brake OFF).
Key to R. H. Electrical Schematic
1
Reducing Valve Assembly
2
Reducing Valve
3
Solenoid Valve
4
Restrictor
11
Interlock Relay
12
Parking Brake Switch
13
Brake Solenoid
14
Operational Solenoid
15
Diode
16
Restraint Switch
17
Door Switch
18
Sequencing E.C.U.
81
Brake Switch Illumination
113
Fuse
114
Fuse
Section E
Hydraulics
9803/8500
Section E
6 - 2
Issue 5
Descriptions
Summary of Contents for ROBOT 150
Page 2: ......
Page 21: ...5 2 Safety Decals cont d Section 2 Care and Safety 9803 8500 Section 2 5 2 Issue 2...
Page 77: ...Attachments Section A Section A 7 7 9803 8500 Issue 1 Backhoe...
Page 97: ...4 3 Section C Electrics 9803 8500 Section C 4 3 Issue 1 Alternator S213570...
Page 123: ...1 1 Section D Controls 9803 8500 Section D 1 1 Issue 1 Safety Restraint Bar S168160 1...
Page 125: ...2 1 Section D Controls 9803 8500 Section D 2 1 Issue 1 Throttle Controls S168150D...
Page 142: ...Hydraulics 9803 8500 Issue 1 4 1 4 1 Descriptions Section E Section E...
Page 145: ...Hydraulics 9803 8500 Issue 2 5 2 5 2 Descriptions Section E Section E...
Page 146: ...Hydraulics 9803 8500 Issue 2 5 3 5 3 Descriptions Section E Section E...
Page 149: ...Hydraulics 9803 8500 Issue 2 5 6 5 6 Descriptions Section E Section E...
Page 152: ...Hydraulics 9803 8500 Issue 1 5 9 5 9 Descriptions Section E Section E...
Page 163: ...10 1 Section E Hydraulics 9803 8500 Section E 10 1 Issue 1 Pumps 168150...
Page 165: ...10 3 Section E Hydraulics 9803 8500 Section E 10 3 Issue 1 Pumps 168030...
Page 167: ...10 5 Section E Hydraulics 9803 8500 Section E 10 5 Issue 1 Pumps 168160...
Page 175: ...11 1 Section E Hydraulics 9803 8500 Section E 11 1 Issue 2 Pumps 167750...
Page 179: ...13 1 Section E Hydraulics 9803 8500 Section E 13 1 Issue 1 Drive Motors 167720 S167720A...
Page 183: ...13 5 Section E Hydraulics 9803 8500 Section E 13 5 Issue 1 Drive Motors S243720 X X S243870...
Page 212: ...18 1 Section E Hydraulics 9803 8500 Section E 18 1 Issue 2 Valves S204980 X X 3 B A 4 2 1 5...
Page 215: ...20 1 Section E Hydraulics 9803 8500 Section E 20 1 Issue 1 Servo Joysticks S167960...
Page 217: ...20 3 Section E Hydraulics 9803 8500 Section E 20 3 Issue 1 Servo Joysticks 167950...
Page 221: ...23 3 Section E Hydraulics 9803 8500 Section E 23 3 Issue 1 Rams S167800...
Page 241: ...1 2 Section F Transmission 9803 8500 Section F 1 2 Issue 2 Tyres and Wheels 167861 167811...
Page 243: ...1 4 Section F Transmission 9803 8500 Section F 1 4 Issue 2 Tyres and Wheels 167851...
Page 253: ...2 1 Section K Engine 9803 8500 Section K 2 1 Issue 1 Removal and Replacement S167990...