Battery; Sensors - Husqvarna Automower 305 Technical Manual

1�13 Battery
The Automower® 305 is equipped with a Lithium-Ion
battery. Compared with a NiMH, for example, Li-
Ion has very good properties, even at high ambient
temperatures. The battery also has low self-discharge,
i.e. it can remain unused for a longer period than, for
example, NiMH without being damaged. Counted
in number of charging cycles, the service life is also
expected to be longer for Li-Ion than NiMH.
Charging is mainly controlled by the transformer.
Normal charge current is 1.0 A. When the voltage
in the battery approaches the nominal voltage of
21.0 V the physical properties in the battery cause
the charge current to decrease. When the charge
current has fallen to 0.3 A, the mower is considered
to be fully charged and charging is terminated. When
the battery is fully charged a rest phase of approx.
60 minutes commences in which the battery is
allowed to cool. This is to ensure maximum service
life for the battery.
Charging is discontinued when the battery has 80%
of its total capacity. Charging the battery to 100%
would reduce the service life of the battery. The
most rational way of using Li-Ion is therefore to stop
charging at 80%.
The maximum capacity utilised is thus 1.2 Ah and not
1.6 Ah which is the battery's total capacity.
6.6 Battery test on page 80 describes how the
battery's condition can be measured.
Charge current
1.0 A
0.3 A
Englsih - 12
1� FUNCTION
Voltage
21 V
3020-005
Capacity
1.2 Ah
1�14 Sensors
There are several different types of sensor in the
mower. Collision sensor (1), tilt sensor (2) and lift
sensor (3) have the task of protecting both mower
and user. Rear (4) and front (5) loop sensors are
used to control the mower within the working area,
to position the mower when docking, track the guide
wire, etc.
3
5
1�14�1 Collision sensor
The collision sensor is the sensor that detects when
the mower has run into a fixed object. When the
sensor is activated, i.e. the mower collides with an
object, the mower waits, reverses and then turns to
continue in a different direction. The body's motion
in relation to the mower's chassis is detected by a
sensor on the control box via a magnet on the body.
1�14�2 Tilt sensor
The tilt sensor is the sensor that detects the mower's
inclination in relation to the horizontal plane. X-angle
indicates the incline forward - back, and the Y-angle
indicates the incline left - right. The value from
the incline sensor is used, among other things, to
compensate the operation of the wheel motors when
mowing on slopes.
1�14�3 Lift sensor
The lift sensor is the sensor that senses whether
the mower is being raised off the ground. This is
done with the help of the mechanical structure and
a magnet in the body at the front of the mower. If
the "lift" signal is indicated, the mower and the blade
disc stop immediately. The mower will then try to
free itself of the obstacle that caused it to lift off the
ground by backing up and turning several times.
1
2
4
3020-006