5 CALIBRATION TEST
The effective seed output may be affected by a change of the
specific gravity and/or size of the seeds. It is therefore
recommended to carry out a calibration test before pro-
ceeding to the application of a new lot of seeds.
A calibration test is carried out as follows:
• Slide the air hose underneath the metering system forwards
(fig. 17).
• Hang a bucket underneath the metering system.
• Set the indicator of the metering device at the value shown
for the output required in the calibration chart, or at such a
value as was established during a previous calibration test.
If the metering device contains seeds and you have to
adjust down to a lower value, you will have to initiate a
calibration test. After consulting “4.3 Seed output set-
ting” turn the indicator towards the intended value while
the cell wheel keeps rotating.
• Fill the hopper.
• Make sure that the bucket is empty.
POLYTRONIC
®
:
• Observe the instructions as laid down in the Operator’s
Manual of the POLYTRONIC control system and select the
option “Empty hopper” in the programming mode.
• Slide the air hose back into position underneath the
metering system and secure this with the lynch pin (fig.
18).
49
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17
18
