Boundary Wire - Husqvarna Automower 305 Technical Manual

Table 2: Colours in the charging station's LED
Colour
Continuous green light
Blue flashing light
Yellow flashing light
Red flashing light
Continuous blue light
Continuous red light
Suggested actions in connection with fault indication,
see 6.4 Trouble shooting loop signal.
1�8 Boundary wire
The strength of the signal in the boundary wire is
constant in a loop that is up to approx. 250 metres in
length. If, however, the loop is longer than 250 metres,
the strength can start to diminish, even though it is still
sufficient.
The strength of the loop signal varies depending on
the distance to the cable. The strength of the signal is
high right next to the cable. The strength subsequently
diminishes the farther away from the cable you get.
More than 15 metres from the loop, the signal is
normally too weak for Automower® 305. Outside the
loop the signal is negative and its strength diminishes
more rapidly. The signal from the boundary wire is
designated the A-signal. See the illustration below for
examples of high and low signal strengths.
The strength of the A-signal also varies along the
boundary wire depending on the proximity to other
parts of the loop. The strength of the signal is affected
1� FUNCTION
Status
All signals are OK
Interruption in the

boundary wire

Break in the guide wire
Break in F-loop
Boundary wire too long
Defective circuit board
100
80
60
by the size of the working area, islands, headlands,
passages and corners. The signal can also be
affected by magnetic objects in the ground or in
nearby walls and buildings. The signal is weakened
in these areas. Examples of magnetic objects are
iron fences, iron girders and reinforcement bars.
Grass areas laid on concrete roofs can therefore
receive a weakened signal.
When the signal is reinforced or weakened, it is
normal that respectively low and high strength in
the signal is not always available along the entire
boundary wire.
The loop signal's reception and amplification in the
mower can also vary by +/- 10% from one mower
to another. This means that at the same point in
an installation, one mower can display A=90 and
another one A=100. The charging station's circuit
board and the mower's loop sensor can give certain
variations between different machines.
If the mower does not detect sufficient strength in
the loop signal when it leaves the charging station to
enable it to follow the guide to a remote area, it will
instead start cutting at once.
120
100
40
Cable
15 m
3012-605
3012-612
English - 9