Installation and use
SEEDER MONITOR MCK 1200
16
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:
1. 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>);
2. 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;
3. measure the distance from the starting point to the end point;
4. 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;
5. 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;
6. 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
A
Wheel revolutions ( ex. 30 )
Start
Stop
Distance covered ( ex. 60 metres )
B
Figure 5. Practical example for calculating the “C” parameter.
