Finding A Break In The Boundary Wire - Husqvarna Automower 305 Technical Manual

6�5 Finding a break in the boundary
wire
A break in the loop wire is normally due to inadvertent
physical damage to the cable, e.g. using a spade while
gardening. In countries with frozen soil sharp stones
that move in the ground can also damage the cable.
Breaks can also be due to too high a tension in the
cable during installation.
Cutting the grass very short immediately after the
installation can damage the cable's insulation. Some
kinds of damage to the insulation only produce a
break several weeks or months later. To avoid this, the
maximum cutting height should always be selected the
first week after the installation and then reduced by
1-2 steps per week until the required cutting height has
been reached.
A cable break can be found by using Husqvarna's
break detection tool or with the manual method that
is described below. Regardless of whether a break
detection tool is used or not, the procedure is the
same; step by step halving the stretch of the wire
where the break might be until there is only a very short
distance left.
A description of how the break detection tool is used
is available in a separate service bulletin. There is a
description below of how to search for breaks without
access to the break detection tool.
1. Check that the LED in the charging station
flashes blue, which indicates a break in the
boundary wire. For further information about
the charging station's LED, see 6.4 Trouble
shooting loop signal on page 76.
2. Check that the boundary wire connections to
the charging station are properly connected
and not damaged.
Englsih - 78
6� TROUBLE SHOOTING
3012-998
3. Disconnect all contactors from the
charging station and then measure the
resistance in the boundary wire. A value
over 20 ohm indicates that there is a
break. If the measured value is less
than 20 ohm and the LED still flashes
blues, the fault is in the charging station's
cabling or the circuit board. See 5.5
Replacing the circuit board, charging
station on page 53.
A2 A1
4. Connect the power to the charging
station. Change the connections between
guide wire and boundary wire in the
charging station.
a) Change connection A1 and Guide.
Check whether the LED is flashing yellow.
b) Put A1 and Guide back in their original
positions. Then change A2 and Guide.
Check whether the LED is flashing yellow.
If the LED is flashing yellow (i.e. the
boundary wire is intact but the guide
wire is not connected) in test a) then the
break is somewhere in the boundary wire
between A1 and the position where the
guide wire is connected to the boundary
wire (thick black line in the illustration
below).
3020-059
3020-060