Machine´s Safety Equipment; General - Husqvarna DXR250 Operator's Manual

General

In this section the machine's safety features and their
function are explained. Concerning inspection and
maintenance, see the instructions under Maintenance
and service.
The machine's safety features can be divided into safety
features for personal protection and those for mechanical
protection. Some of the safety features provide both
mechanical and personal protection.
WARNING! Do not modify the machine's
!
safety devices and check regularly that
they are working properly. The machine
must not be driven if protective plates,
protective covers, safety switches or
other protective devices are not fitted or
are defective.
Personal protection
Indication of zero position
If either of the joysticks is in an operative position when
the remote control is started, the function will be blocked.
The operator is informed of this by means of an error
message appearing on the screen. To reset the function,
the remote control must be turned off and on again.
The function also protects against faults in the
potentiometer or cable breaks.
Signal voltage limitation
Signal voltage limitation prevents the machine executing
unexpected movements in the event of a cable breaking
or a short-circuit.
The voltage level of the control signals is limited to within
a maximum and minimum value. If the voltage level falls
outside the permitted interval, the machine stops.
Joystick guard
The safety feature reduces the risk of unintentionally
moving the machine by locking the control circuit if the
joysticks have been in neutral for three seconds.
The control circuit is activated by means of the left button
or thumb switch in down direction on the right joystick. It
is activated when the button is released. This guards
against fixing the button in an active position.
Radio block
If the remote control has lost connection for two minutes
the electronic unit in the machine is blocked to radio
signals. A message appears on the display. Confirm the
message to return to normal operation.
The safety feature ensures that the operator knows which
machine will start and that the correct remote control is
being used for the machine. This is particularly important
when there are several machines at the same workplace.
16 – English
MACHINE´S SAFETY EQUIPMENT
Identity code
The remote control and the machine are connected by
means of a pre-programmed ID code. The ID code
ensures that the right remote control is used for the right
machine.
If several machines are used at the same workplace there
is a risk of mixing up the remote controls.
Switch on the current to the remote control and the
machine. Press the horn to see which machine is
connected to the remote control. The machine will beep
and flash three times. Do not activate the remote control
before you have ensured that the correct machine is being
operated.
When steering the machine using cables, the ID code is
suppressed and the same remote control can be used for
different machines if these have the same control system
version.
Automatic frequency hopping
In the event of interference in the communication, the
frequency changes automatically to guarantee
interference-free transmission.
Emergency stop/machine stop
The machine stop on the remote control and the
emergency stop on the machine break the power to the
electric motor.
Protective earth
The machine and its components are connected to
grounding conductors in the power cable. If there is a
fault, a fuse is tripped and the current is disconnected.
The machine must be connected to a power point with a
protective earth. If there are no grounding conductors, or
if they are connected incorrectly, have come off or are
loose in a terminal, the current will remain connected and
touching the machine can be highly dangerous.
If there is reason to believe that the protective earth has
been damaged, the machine must be turned off and the
power cable removed until such time as the protective
earth has been restored.
Always connect the machine through an ground fault
circuit interrupter with personal protection, i.e. an ground
fault circuit interrupter that trips at an ground fault of 30
mA.
Hydraulic brake
Hydraulic motors are used when moving the machine. All
hydraulic motors are fitted with brakes. These hydraulic
motors contain counter balance valves that prevent
uncontrolled flow through the motor, e.g. when
manoeuvring down a slope or when the machine is
parked. The counter balance valve closes the tank
opening when the drive motors are not being operated.
Mechanical brake
The machine's drive motors are equipped with a
mechanical parking brake. The machine is braked until its
drive function is activated.