Hayter Mowers 101 88 90-26 - Manual (Page 7)

6
– English
The sensor is sensitive to moisture and dirt. If, for example,
grass sticks between the sensor's pins this will cause signal
leakage and the lawn mower will possibly signal that it cannot
sense a signal from the loop cable (3 beeps/second). The
unused (smaller) pin can be cut off and insulated using silicon if
the problem frequently recurs.
The part of the cable harness that runs from the sensor is
connected to terminals 15 and 16 on the connector X1 on the
circuitboard. (Arbitrary pole reversal.)
TROUBLE SHOOTING
Drive motors
Two, 12 V DC motors with reversible direction of rotation are
used to drive the lawn mower forwards. The two drive motors
can rotate in different directions at the same time to give the
lawn mower a tight turning circle and increase manoeuvrability.
A gearbox is engaged after the drive motors to give the lawn
mower increased traction. The speed is registered by a tachom-
eter which is connected to the motors. The speed of the motors
is then governed by the microprocessor.
The cables from the drive motors are connected to the connec-
tor X9 (left) and X8 (right) on the circuitboard in the box. The
voltage to the drive motors should be 12 V.
Red cable (+) and black cable (-) are the supply cables. These
can be fed with 12 V for test driving. The other three cables are
used to control the motor.
Supply cable
Sensors
A sensor (coil) is mounted on top of the front bracket between
the front wheels, see the diagram below, so that the lawn
mower can sense the electromagnetic field emitted by the loop
cable.
The lawn mower uses two different systems to sense the
electromagnetic field:
1. The lawn mower should, with a loop length of 300 m – at a
distance of max. 35 meters from the loop cable (see
diagram) sense that the loop cable is generating an
electromagnetic field, see diagram, (with a 500m loop
length - max 25 m). If it does not sense the electromagnetic
field an error signal, 3 beeps/sec. is sounded.
NOTE! The maximum cutting area to achieve a good
cutting result is approx. 1200m
2 .
2. The lawn mower should sense the increase in the electro-
magnetic field as it approaches the loop cable and because
of this turns just in front of the loop cable.
Sensor
The cables connected to the rivet are connected to connector
X5 on the circuitboard.
Cable
A copper rivet and a zinc plate form a galvanic element that
when wet generates a voltage of 0.7V, which can be measured
on the cables on the inside.
The moisture sensor only measures moisture in long grass, that
is, it will not react to short, moist grass.
Moisture sensor
Using the keyboard (press C0) you can activate the moisture
sensor which is located under the box so that the lawn mower
can determine whether the grass is too moist to give an accept-
able mowing result.
Eng-SOL VERK 98-01-15, 10.07 6