Kalmar ContChamp DRD S Series, Technical Handbook

Page: 61 / 298

ContChamp DRD-S
Technical Handbook
ECU 1
04 Lever Steering
29 S. Grupp 20
9407
04-10
Lever steering characteristics
Also applies to Module 06, Mini-steering
The maximum wheel displacement from maximum lever move-
ment is determined by the speed of the truck. Wheel displace-
ment decreases when speed increases. The reduction in
displacement follows a curve with three break points, see dia-
gram.
This curve determines the steering sensitivity of the truck. The
standard factory setting is as shown in the diagram, i.e., full wheel
displacement at 5 kph, 65% displacement at 10 kph and 40% dis-
placement at 15 kph. All of these levels corresponding to full
movement of the steering lever.
It is possible to alter the break points and the displacement, see
INITIATION MODULE 04. One reason for altering lever steering
characteristics can be that a new operator would like less wheel
displacement at a certain speed - the truck feels “smoother” to
steer. A more experienced operator, on the other hand, may like
a quicker steering response, which allows a faster pace of oper-
ation.
Alteration of the Steering lever output signal
It is possible to alter the output signal from the Steering Lever to
follow two different curves - linear or logarithmic
The logarithmic curve provides less sensitive steering.
In the ECS SERVICE Technical Handbook, under Initiation Mod-
ule 04, a description can be found as to how to choose between
the two curves.
Alteration of the Mini-steering device output signal
The number of turns that corresponds to normal steering wheel
movement can be set, see Technical Handbook ECS SERVICE,
Initiation Module 06.
Monitoring of steering lever & wheel angle sensor
If a fault occurs in the lever steering system - sensor, steering le-
ver, cables - an alarm is generated by the ECS. Lever steering is
frozen, i.e., the wheels remain at the current steering angle and
the operator must therefore use the steering wheel. After such a
fault, re-calibration must be carried out in accordance with the in-
structions in the Calibration section.
Checking the sensors and activator on the steer-
ing column
Two sensors on the steering column monitor steering wheel
movement. The senors are activated by an activator with four
cams on the steering column. See the illustration of included
units. When a certain movement of the steering wheel occurs, le-
ver steering is disconnected.
The sensors and activator must be regularly checked during
service. If a fault occurs with the sensors, there is a danger that
the truck will go straight forward.
1. Open ECU 1 so that the LEDs are visible.
2. Locate LE25 and LE26, see ECU 1 Circuit board.
3. Turn the steering wheel and at the same time, check LE25 and
LE26. They should light alternately, with a certain overlap, as
per the curve.
Wheel displacement at full lever
movement.
Values as per INITIATION 04,
menus 3-7
BP1
BP2
BP3
100%
65%
40%
0 5 10 15 Km/hr.
WARNING!
If wheel displacement is set too high at higher speeds,
there is a risk of the truck tipping. Any alteration of lever
steering characteristics must be made with great care.
6
5
3
2
1
4
8
7
7
8
1. Output signal
2. Stop voltage
3. Start voltage
4. Middle position
5. Free-play zone
6. Lever movement
7. Linear output signal
8. Logarithmic output signal
LE25
LE26
Anti-clockwise turning: LE25 lights first
Clockwise turning: LE26 lights first