PDF Workshop Manual Still RX20-14 RX20-16 RX20-18 RX20-20 Electric Truck - 2 MB
This workshop literature is the comprehensive service manual for the Still RX20 series electric forklift trucks, including models 14, 16, 18, and 20.
It contains all the technical data, repair procedures, and diagnostic information needed by service technicians.
From battery maintenance to controller diagnostics, this manual covers every aspect of forklift repair.
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--- Page 1 ---
Workshop literature
Electric trucks
RX20-14
RX20-16
RX20-18
RX20-20
6219 6220 6221 6222 6223 6224
6225 6226 6227 6228 6229 6230
6231
56368010001 EN - 05/2018
--- Page 3 ---
Table of contents
g
30 Chassis, bodywork and fittings
Chassis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30- 1
Battery door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30- 1
Battery door sensor 1S27 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30- 2
Overhead guard bearings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30- 2
Counterweight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30- 4
Counterweight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30- 4
Hoods and panelling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30- 5
Panels on the driver's compartment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30- 5
Overhead guard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30- 8
Repairing the roof panels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30- 8
42 Steering system
Hydraulic steering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42- 1
General technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42- 1
Steering system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42- 2
Steering angle sensor 3B1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42- 5
Steering turntable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42- 6
General technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42- 6
Functional description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42- 7
Steering angle sensor 3B2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42- 8
Removing/installing the steering axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42- 9
Combined axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42- 12
General technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42- 12
Functional description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42- 13
Removing/installing the steering axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42- 15
Adjusting the steering angle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42- 17
Wheel hub - Replacing the bearings and sealing ring . . . . . . . . . . . . . . . . . . . . . . . . . 42- 19
Disassembling the steering cylinder and track rod . . . . . . . . . . . . . . . . . . . . . . . . . . . 42- 21
Replacing the axle stub, bearings and wiper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42- 23
Steering cylinder, changing the seals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42- 25
Steering angle sensor 3B2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42- 27
50 Operating devices
Accelerator pedal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50- 1
Accelerator pedal, generation 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50- 1
Dual pedal, generation 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50- 3
56368010001 EN - 05/2018 IX
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Product information 00
Safety information
Jacking up the truck, front
General
The truck has to be jacked up for various mainte-
nance tasks.
DANGER
If the truck is not jacked up correctly, the truck can fall
and cause fatal injuries.
– Park the truck securely.
– When jacking up the truck, always secure it against
rolling away or tipping over by using the appropriate
supports (e.g. wedges or supporting blocks).
– Use only hoists with sufficient load capacity.
– Only jack up the truck on a level surface.
– Only jack the truck up at the specified points.
WARNING
Risk of injury!
Apply the parking brake and set the key switch to OFF
before jacking up the truck.
Jacking up the truck
– Park the truck securely on level ground.
– Turn the key switch to OFF.
– Apply the parking brake.
– Remove the forks or push them together in the
middle.
For a good level of stability, support blocks must
be placed under the chassis on both sides. For
this reason proceed as described one side after
the other.
– Lift the fork carriage so that the hydraulic jack
can be placed on the outer mast.
– Jack up the truck until the wheels are no longer
in contact with the ground.
56368010001 EN - 05/2018 00-5
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Service 01
Maintenance
Maintenance - 3000 hours/every two years
At operating hours Carried out
3000 6000 9000 12000 15000
Note
Perform all 1000-hour maintenance work.
Power unit
Change the gearbox oil in the drive wheel unit.
Replace the bleeder screws on the drive wheel units.
Hydraulics
Change the hydraulic oil.
Replace the return line filter and the breather filter.
Variant: Replace the high-pressure filter.
56368010001 EN - 05/2018 01-5
--- Page 6 ---
Diagnostics 02
Working with DiaMon
Reading out and clearing the error
list
– Connect the notebook to the truck and start
the truck diagnostics, see the chapter entitled
"Introduction to DiaMon":
F2: Diagnosis
▼
Jobs
▼
Select action (4)
▼
Execute 1 F2: Diagnosis
2 Jobs
3 Execute
Read error list Error lists
4 Read error list
Various types of error lists are available for
4 Clear error list
selection: 4 Read error ring buffer
1 Active errors
Lists all errors that are currently active
2 Errors since the last reset
Lists all errors that have occurred since the
truck was switched on.
3 All stored errors
Lists all errors that have occurred since the
error list was last cleared
The relevant error list is then displayed, depend-
ing on the type of error list selected. All errors
from all control units are displayed in this list. It is
not possible to select individual controllers.
Clear error list
The error list for all controllers will be deleted. It is
not possible to select individual controllers.
Read error ring buffer
The option to read out the error ring buffer de-
pends on the software version installed in the
truck. More information about this can be found
in the "Truck software overview" document
• Error ring buffer: general
The latest 256 errors from the truck control unit
(MCU, TCU are displayed (error group A).
• Error ring buffer: converter
The latest 256 errors from the converter are
displayed (error groups D and E).
For more information, see chapter "60 - Error ring
buffer"
56368010001 EN - 05/2018 02-5
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Electric motor 11
a
Traction motor
General technical data
Traction motor 6219 - 6131
Manufacturer Linde (LIPO)
Designation EM112-01A65F28 A54
Weight of left-hand traction motor [kg] 75.5
Weight of right-hand traction motor [kg] 73.7
Operating voltage [V] 48
Three-phase asynchronous motor with
Motor type
cage rotor
Circuit Delta
Rated voltage (nominal) [V] 28
Rated current (nominal) [A] 195
Rated speed (nominal) [rpm] 2310
Maximum speed [rpm] 5900
Rated output (nominal) [kW] 6.5
Peak output [kW] 9.7
Mode of operation (nominal) S2 (60 min)
Protection type IP 54
Insulation class F
Cooling Convection
Sensor system
Temperature sensor NTC type Z-
Speed sensor Pin sensor
.
Electrical connections
AE18-11
Plug Designation
1M2 Traction motor, left (FM2)
1U25/U-V-W Twin converter, left
X12 Speed sensor on 1U25
X13 Temperature sensor on 1U25
1M1 Traction motor, right (FM1)
1U06/U-V-W Converter, right
X10 Speed sensor on 1U06
X11 Temperature sensor on 1U06
.
56368010001 EN - 05/2018 11-1
--- Page 8 ---
Mechanical drive axle 22
a
Drive axle AE18-11
General technical data
Drive axle
Manufacturer Linde (LIPO)
Drive axle AE18-11
Drive wheel unit GR2E-07
Traction motor EM112-01A65F28 A54
Total weight [kg] 204
Permissible axle load [kg] 4884
Maximum speed [km/h] 20
Tyres (alternative) 200/50-10
Dynamic tyre radius [mm] 229
Track width [mm] 942 / 990
Maximum wheel speed [rpm] 232
Gear ratio [i] 25.45
Brakes
Clearance [mm] 0.8+0.2, set under an assembly force of 60 Nm (6 kg)
Brake lever for bearing axle [Nm] 25
Static braking torque [Nm] 4200
With force F1 [N] 1700
Dynamic braking torque [Nm] According to characteristic curve
With force F2 [N] According to characteristic curve
Oil content [l] 0.2+0.02
Brake oil Shell Spirax S4 ATF HDX
Oil change interval No oil change necessary. Oil is suitable for lifetime use
Drive wheel unit
Slotted nut M60x2-981
Slotted nut on drive wheel unit [Nm] 650+50
Secured with FK2 WN12612
Mounting screw, 2nd planetary
[Nm] 25 1 x M8x20-8.8-4762 socket head screw
gear
Gearbox oil, per side [l] 0.3 SAE 80W-90 API-GL4
Oil change interval Once at 1000 hours, then every 3000 hours
Tightening torques and connecting elements
Wheel screw, per wheel [Nm] 210 5 x spherical collar bolts
Screw joint between the drive axle 6 x hexagon head screws M20x40-8.8-933
[Nm] 385
and chassis, per side 6 x washers 20-FST-A2C
Screw joint in traction motors,
[Nm] 275 4 x M16 x 60-10.9-4762 socket head screws
central
Screw joint in drive wheel unit, per
[Nm] 275 7 x M16 x 45-10.9-4762 socket head screws
side
Oil top-up on the gearbox [Nm] 70 M18x1.5–6149-V80
Oil drain on the gearbox [Nm] 15 M10x1-Y6149-MA
Oil level check on the gearbox [Nm] 15 2 x M10x1–6149-V80
Bleeder valve for brakes [Nm] 10
56368010001 EN - 05/2018 22-1
--- Page 9 ---
Mechanical drive axle 22
Drive axle AE18-11
– Fit the inner retaining ring (3) and outer
retaining ring (2).
– Wet the surface of the shaft with brake oil.
Press the new shaft seal (1) into the bearing
flange.
– Press on the front bearing using assembly
sleeve WM451. Press the bearing in over the
bearing inner ring, otherwise the bearing will
be damaged.
Traction motor - Installing the rotor
– First, insert the washer and then the shaft
washers (2 pieces) into the motor housing.
– For the bearing shield installation, mark the
position of the rotation lock on the motor
housing.
56368010001 EN - 05/2018 22-11
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Chassis, bodywork and fittings 30
a
Chassis
Battery door
Frame Battery door
1 Battery lock 5 Door holder
2 Catch bolt with spring element 6 Door lock
3 Bump stop 7 Door opener
4 Hinge 8 Spring element
Installing the door holder
– Lightly grease the bolt. Insert the bolt with
the conical spring washers into the lower
strut. The concave sides of the conical spring
washers face each other.
– Tighten the bolt (left-hand thread) to a tighten-
ing torque of 40 Nm.
– Engage the multiple toothing on the tappet on
the pins in such a way that it lies as close as
possible to the threaded hole in the door.
– Continue to the tappet anticlockwise until it
1 Tappet
fully covers the threaded hole.
2 Bolt
– Screw the tappet with the screw and washer to 3 Conical spring washers
the door. 4 Screw, washer
56368010001 EN - 05/2018 30-1
--- Page 11 ---
Steering system 42
a
Hydraulic steering
General technical data
Steering unit
Steering unit 3-wheel 4-wheel
Manufacturer Danfoss
Designation OSPC 50 OSPC 100
Delivery rate [ccm/rev] 50 100
Pressure relief valve [bar] 140...150 135...150
Shock valve [bar] 200...220 200...220
Transmission ratio
Steering wheel rotation, stop to stop
Steering speed [rpm] 400...800 400...1600
Tightening torques
P, T, R, L, LS [Nm] 80-4 Pipe union L10-M18x1.5
.
Priority valve
Priority valve
Manufacturer Danfoss
Designation OLSP 80
Delivery rate l/min 80
Pre-load pressure [bar] 7±1
P, EF, maximum pressure [bar] 290
CF, LS, maximum pressure [bar] 175
Load signal Dynamic
Tightening torques
P, hydraulic pump [Nm] 9+1 4 x socket head screws M6x40-8.8
LS, Load Sensing [Nm] 30-1.5 Pipe union M12x1.5/M18x1.5
EF, directional control valve (high-
[Nm] 100-5
pressure filter)
CF, steering [Nm] 80-4 Pipe union L12ME-ST
.
56368010001 EN - 05/2018 42-1
--- Page 12 ---
Steering system 42
Steering turntable
Screw in the screw joints up to the blue coating.
Then screw the screw joints into position using a
minimum of three to a maximum of four revolu-
tions. Do not unscrew the screw joints.
– Mount the wheels.
– Lower the truck.
– Tighten the wheel nuts.
– Guide the cable for plug X29 upwards into the
counterweight.
– Connect plug X29.
– Fit the sheet metal cover.
– Install the battery in the truck.
Bleeding the steering
– Warm up the truck.
– Then steer fully from stop to stop at least five
times.
56368010001 EN - 05/2018 42-11
--- Page 13 ---
Steering system 42
Combined axle
– Slide the washer (46) onto the wheel shaft and
knock in the slotted spring pin (3).
– Tighten the new prevailing torque nut (2).
CAUTION
Observe the specified tightening torque.
The thread of the wheel shaft and prevailing torque nut
must be clean and free of grease!
– Fill the hubcap (1) completely with grease. Fit
the hubcap on the wheel hub and knock it in
using a soft-faced hammer.
Disassembling the steering
cylinder and track rod
Disassembly
– Remove the steering axle. See the chapter
entitled "Removing/installing the steering
axle".
– Place the steering axle on a suitable pad. Set
the steering to the straight-ahead position.
– On the right-hand side, unscrew the steering
angle sensor together with the transmitter.
– Knock out the upper slotted spring pin (1) on
both sides. Press out the bolt (2).
NOTE
When pushing out the bolt, support the steering
arm from below to prevent it from being damaged.
– Unscrew the track rods with the spherical
bearings and seals from the steering arms.
56368010001 EN - 05/2018 42-21
--- Page 14 ---
Operating devices 50
Accelerator pedal
Errors
Voltage increase too small The maximum speed is not reached
No problem for the evaluation
► The maximum speed is reached but not exceeded.
Voltage increase too large
► The controller ignores the end range of the voltage increase
(dead travel)
Voltage increase significantly too large Detection of breakdown with corresponding error message
.
Dual pedal, generation 2
Accelerator
1 Pedal, forwards 3 Lubrication points for maintenance
2 Pedal, reverse 4 Potentiometer 1B3
The accelerator comprises two mechanically
connected accelerator pedals that move in
opposite directions. When the accelerator pedal
is pressed, the potentiometer 1B3 regulates the
driving speed.
Technical data
Plug 6-pin MQS (AMP)
Supply voltage 5 V ± 10%
Protection class IP64
Temperature range -40°...+65°C
.
Electrical connections
1B3/1 GND 1B1/1 X47/49
1B1/2
1B1/3
1B3/3 Accelerator signal, channel 2 1B1/4 X47/15
56368010001 EN - 05/2018 50-3
--- Page 15 ---
Operating devices 50
Electric parking brake
Function and layout
The electric parking brake (ELF 2) actuates the
mechanical multi-disc brake on the drive axle via
a brake cable. It makes sure that the brake is
applied automatically when the operator leaves
the truck.
The ELF 2 can be released and applied via the
toggle switch (1). All the necessary enable flags,
such as seat switch and switch lock, must be
present in order to release the brake. The ELF 2
also offers automatic driver assistance functions,
which apply and release the brake automatically
in certain situations. In emergency operation or
during transport without a battery, the ELF 2 can
be operated manually via the hand wheel (11).
Layout
1 Toggle switch 9S26 with LED 7 Controller
2 Hose with grease supply for continuous 8 Panelling
lubrication 9 Console
3 Plug X506 10 Tappet
4 Plug 1S3 11 Hand wheel for emergency actuation
5 Automatic cable adjustment 12 Joining plate
6 Safety clip 13 Limit switch 1S3
The ELF 2 consists of a drive unit with integrated
controller (7). The ELF 2 is attached to the front
structure of the truck by means of two screws.
56368010001 EN - 05/2018 50-13
--- Page 16 ---
Operating devices 50
Hydraulic actuation
Joystick 4Plus
Layout
The Joystick 4Plus is an operating device built
into the right-hand armrest of the driver's seat.
Within the Joystick 4Plus there are various
controls that that the driver can activate using
his right hand.
NOTE
Modified control functions:
• Lighting in line with the German road traffic
licensing regulations always only with travel
direction selector and indicator module.
• The emergency off switch is located in the 1 Joystick
2 LED display
steering column as standard.
3 Housing inlay
4 Support for the display and operating unit
5 Panel
6 Upper shell
7 Control symbols
8 Lower shell
Functions
The shift key F can be assigned different func-
tions during the parameterisation process. For
example, switching over the control axles. The
switchover can be performed only when all axles
are in the neutral position. The 5th hydraulics can
then be actuated, for example.
Technical data
CAN open as standard;
CAN bus integrated into the red
CAN bus
Sensors 1 Hall sensor per axle 1 Horizontal rocker button
2 Horn button
Software Device ID "I"
3 Shift key F
Protection class IP 65 4 Drive direction
Temperature range -30 °C to +85 °C 5 Slider
.
5 LED display for clamp release
Electrical connections
X100
X100/1 CAN_rt_H
X100/2 CAN_rt_L
X100/3 CAN_rt_GND
X100/4 12 V
X100/5 Unassigned
X100/6 Unassigned
.
56368010001 EN - 05/2018 50-23
--- Page 18 ---
Display elements 56
Display
Display and operating unit ABE 3
ABE 3 for trucks with hand lever
ABE 3 for trucks with servo hydraulics
Technical data Electrical connections
CAN open as standard ABE 3
CAN bus
ABE CAN bus (orange) X49/1 CAN or H (orange)
Software Device ID "J" X49/2 CAN or L (orange)
Operating voltage 12 V (9...18 V)
X49/3 12 V
Current draw 0.5 A X49/4 CAN or GND (orange)
Current draw with
X49/5 X50/5, enable diagnostics
display heating 1.5 A
activated X49/6 X50/6, TRX-P
Protection class X49/7 X50/7, TRX-M
Temperature range -35...+75 C X49/8 —
4x M5x10-08.8-ZNB X49/9 —
Mounting on armrest
2.1 Nm X49/10 —
Mounting on A-column .
.
56368010001 EN - 05/2018 56-3
--- Page 19 ---
Electrics/electronics 60
Electrical checks
LED-X27 or LED X93 LED (4) illuminate in red
and go out slowly.
– Use the multimeter to check the voltage in the
intermediate circuit.
If the voltage is below 3 V, the intermediate circuit
is discharged.
56368010001 EN - 05/2018 60-9
--- Page 20 ---
Electrics/electronics 60
Wiring
Terminal resistance and
Components CAN bus 12-V supply
measurement
X89 Lithium-ion battery Green 120 Ω not possible 12 V_X46:104
X88 VDI 4458 interface Violet 120 Ω not possible 12 V_1F8_X47:26
.
Diagnostic connector X50
Technical data
X50 Assignment
X50/1 CAN ge H (yellow)
X50/2 CAN ge L (yellow)
X50/3 12V_1F8_Bus
X50/4 CAN ge GND (yellow)
X50/5 X49/5, enable diagnostics
X50/6 X49/6, TRX-P
X50/7 X49/7, TRX-M
The pins X49/5 .... X49/7 are intended for quick
loading of the ABE parameters. Quick loading
via an Ethernet connection. This function is
currently active only for the production variant.
The Ethernet connection is not yet available for
the servicing variant
56368010001 EN - 05/2018 60-19
--- Page 21 ---
Electrics/electronics 60
Electrical system
Fuses
Fuse box
The fuse box is fitted with 32-V and 80-V fuses.
All of the 80-V fuses are located in the battery
voltage circuit. The 32-V fuses are located in the
on-board power supply circuit.
NOTE
Observe the voltage range of the fuses!
Fuse Connection
F15 30 A / 80 V Green 12-V reserve
F16 5 A / 80 V Brown Fan
F21 20 A / 80 V Yellow Voltage converter U2
F22 20 A / 80 V Yellow Voltage converter U3
F23 5 A / 32 V Brown Voltage converter, emergency off switch
F24 20 A / 80 V Yellow Voltage converter U4
F28 15 A / 80 V Blue Voltage converter U1
F36 10 A / 32 V Red MMI 12 V
F37 10 A / 32 V Red MMI 24 V (after voltage converter U4)
F38 30 A 32 V Green CPP 4
F39 10 A / 32 V Red 24-V reserve for restraint system Sauermann
1F8 5 A / 32 V Brown MCU, 12-V CAN bus, red
1F9 5 A / 32 V Brown 12-V CAN bus, blue
1F10 10 A / 32 V Red 12-V CAN bus, red
1F15 5 A / 32 V Brown 12-V relay 1K18, 1K4 (ABE 3, TDU)
1F16 20 A / 32 V Yellow 12 V for servo hydraulics (FIT), switchover of release valve
5F11 30 A 32 V Green CPP 1
56368010001 EN - 05/2018 60-29
--- Page 22 ---
Electrics/electronics 60
Sensor system
LED lift height sensor 6B32
Function
Not yet available
NOTE
If the truck is to be converted to use optical lift
height sensor 6B32, the lift height switch 7B41
and the support must be removed from the outer
mast.
Technical data
Technical data
Supply voltage 12 V
Operating voltage, UB 10 to 30 V
CANopen,
Interface
250 kBit/s
Measuring range 0.05 to 14 m
Light emitter LED
Ambient temperature -35 to +55 °C
Protection type IP 65
Electrical connection
4-pin AMP plug
7B42/1 CAN_rt_H CAN distributor 6X73/1
7B42/2 CAN_rt_L CAN distributor 6X73/2
7B42/3 12V_1F10_Bus CAN distributor 6X73/3
7B42/4 CAN_rt_GND CAN distributor 6X73/4
.
Parameterising
The required function must be parameterised for
all retrofitting and conversions. Parameterisation
is performed using the truck diagnostics on the
notebook.
Parameterisation via diagnostics
► F3: Setup
► Assistance systems
A truck restart must always be performed after
parameterisation.
Calibration
Once calibration is complete, error messages
may be displayed.
Calibration via the display-operating unit Calibration via diagnostics
► Service password level ► F2: Diagnosis
56368010001 EN - 05/2018 60-39
--- Page 23 ---
Electrics/electronics 60
Cooling system
Since there is no filter to prevent dirt from being
drawn in along with the fresh air, it is to be ex-
pected that the cooling fins will become dirty.