52
53
Maintenance of the
metering unit
The metering unit does not require any special
maintenance.
In order to avoid repair related downtimes, both
the metering unit and the drive motor should be
cleaned and subjected to a function test after the
end of the season.
The bearings in the side cover in particular
can be damaged or may become hard-moving
because of dressing dust.
If necessary keep bearings in stock and replace
in due time.
2
1
2
Drive motor
1 Screws
1 Radial seal and bearing
Plug assignment on the motor
In case of cable break or repair work on the plug,
the cables can be connected by soldering.
However, the use of crimping contacts is
recommended.
Pin No.
Cable
1
blue
2
red
3
white
4
brown
5
green
6
yellow
Metering unit with injector fall
sluice
The metering units in machines with normal
hopper and injector fall sluice are equipped with
a lid (V2A) with machined recesses.
During operation the injector nozzle is exposed
to vacuum. This lid adds additional air to the
air flow.
Metering unit with lid for injector nozzle
The adjustment between injector nozzle and lid
works up to a max. possible seed quantity.
Exceeding this quantity results in a dynamic
pressure at the injector nozzle. This may blow
seed out through the perforated plate, which
leads to a strip-like emerging of the seeds.
These grains are visible on the surface of the
field before they are covered by the packer or
the harrow.
Under extreme conditions overpressure can
block the seed flow in the hopper. This causes
seed failure.
NOTE
Always check the function of the pneumatic
system and the seed placement but especially
at high placing quantities and working speeds.
No grains should remain on the surface of the
field.
If grains are blown out, the fan speed needs to
be increased (temporarily up to 4000 rpm)
or the working speed must be reduced until the
injector system works correctly again.
