Ground Drive
– Metering Drive System
Page 63
05/06
High Rate Sprocket Ratio
When wishing to meter high rates of seed
or fertilizer it may be necessary to increase
the speed range of the metershaft. This is
done by altering the sprocket ratio from the
standard rate to a
‘High Rates’
sprocket
ratio.
Generally this change in ratio would only
occur when the machine is being used for
deep banding and a reduced number of
meterwheels are in place. The ‘Variator
Setting Guide’ will alert the operator when
this change may be necessary.
DO NOT
use a ‘High Rates’ sprocket ratio if
not recommended. Refer to ‘Variator
Setting Guide’ (pages 41–55) for its
appropriate use.
To Change Sprocket Ratio on a Ground
Drive Seeder
1. Remove the chain on the right hand side
of the meterbox that connects the
agitator shaft and the meterwheel shaft.
2. Using an allen key loosen the grub
screws that retain the nylon sprockets.
Two screws per sprocket.
3. Remove both sprockets and swap their
location. This will effectively more than
double the speed of the metershaft i.e.
the big sprocket now driving the little
sprocket. (Fig. MD4).
4. Tighten the grub screws when the
sprockets have been correctly located.
Check that the metershaft handle still
fits and that the 2 sprockets are in line.
5. Refit the chain and check that the
system turns freely.
NOTE:
Increasing the speed of the
metershaft also increases the load on the
variator. It is therefore not recommended to
run the seeders metering system in this
‘High Ratio’
all the time. Variator damage
may occur depending on the material’s
resistance.
Fig.MD4 High Rates Sprocket Ratio.
Reversing the sprockets will give you the
standard sprocket ratio.
ALWAYS
run the
system in this mode for normal seeding
operations. (Refer Fig. MD5).
Fig.MD5 Standard Sprocket Ratio .
