User’s manual
SEEDER MONITOR MCK 800
17
6.2.1 Practical example for calculating the C parameter to be
programmed
As anticipated previously, in the “C” parameter you have to program the number of
impulses the proximity sensor has to send to the Tachometer every 100 linear meters
the machine works. Therefore, you must calculate how many reference points will
pass in front of the sensor every 100 linear meters. In this example we assume that
the proximity sensor is assembled so as to sense a magnet fixed to one of the wheel
bolts (see Figure 5):
place the machine on a flat ground and mark clearly (with a piece of chalk, for
instance) the outer side of the tire in the exact place where it touches the ground
(figure 5 – ref. <
A
>);
take as your reference on the ground a point that corresponds to the mark you
made on the tire (starting point. Figure 5 – ref. <
A
>) and move the machine
slowly forward until the wheel has made an exact number of rotations, for our
example let’s say 30, then stop the machine (end point. Figure 5 – ref. <
B
>); to
obtain highest precision of setting you’ll need to go at least 50 meters;
measure the distance from the starting point to the end point;
let’s assume the distance you measured is 60 meters: 60 meters divided by 30
rotations gives 2 meters as the measure of each rotation of the wheel;
dividing 100 meters (reference distance for parameter “C”) by 2 meters (wheel
circumference) the result is that the machine wheel makes 50 rotations in 100
meters;
now you only have to multiply the number of
rotations the wheel makes in 100
meters
(according to our calculation, 50) by the number of reference points the
sensor detects at each rotation of the wheel (according to our example, 1 bolt):
the result is the number of references/impulses that are detected per 100 linear
meters (according to our example: 50 x 1 = 50). Insert this value for the “C”-
parameter programming;
Parameter “C”
=
100 metres
x
N° wheel references
Wheel circumference in metres
Figure 5. Practical example for calculating the “C” parameter.
A
Wheel revolutions ( ex. 30 )
Start
Stop
Distance covered ( ex. 60 metres )
B
