IKA A 11 basic - Manual (Page 16)

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Caution: Liquid nitrogen cooling is not permitted in grinding beaker A 11.4 (250
ml beaker made of polycarbonate).The beaker would break during cooling.
Check whether the voltage specified on the type plate matches the mains voltage
available. The power socket used must be earthed (protective earth conductor
contact). If these conditions are met, the device is ready to operate after plugging
in the mains plug. If these procedures are not followed, safe operation cannot be
guaranteed and / or the equipment may be damaged.
Observe the ambient conditions (temperature, humidity, etc.) listed under “Technical
Data”.
The grinding container in figure 1 can be unscrewed and removed by rotating it
counterclockwise. The drive section can be turned off on the guard ring (item 8).
The grinding container is filled with a suitable material. It is essential at this point
not to fill the container higher than the maximum filling height (up to the lower
edge in the grinding container, see figur 1). Filling the container to a higher level
will result in interfering with the operation, which will overload the mill. The filling
quantity can be reduced down to the „uniform grain size“ (in other words minimum
quantities are also possible).
Note: Smaller filling quantities (for example only about 50 - 80% of the maximum
filling quantity) can be pulverized more quickly, the final granularity is finer, the
range of granularity is smaller and there is less heating up of the grinding materials.
It is better to reduce a large quantity of grinding materials in two or three
portions. The actual grinding time is only barely longer, but the grinding results are
considerably better.
Bulky grinding material (for example hay, etc.) can also be filled up higher then the
lower edge, but no more than about 20 mm below the upper edge of the grinding
container. The loose grinding material is forced into the grinding zone when the
drive is pushed in.
The filling grinding container is screwed in onto the drive up to the stop (you can
hear a soft click just before reaching the stop).
When electrical power has been connected, you can begin with the grinding
procedure. Grasp the hood with one hand, press the on/off - switch with your
Commissioning
thumb (figure 2), and the mill starts. Pressing the drive down softly and slowly in
the axial pressing direction forces the pulverization tool into the grinding material
(pressing on one side only can tilt the drive, which could result in premature wear
and tear on the shaft seal).
When the pulverization tool engages the grinding material, the speed of the motor
decreases. The reduction in rpms is audible. If the reduction in speed is very pronounced,
the speed of the drive should be increased to be able to insert pulverization tool
into the grinding material at nominal speed. Depending on the grinding material,
it may be necessary to repeat this procedure serval times. If the speed remains
relatively constant while the pulverization tool is being lowered and raised back up,
the grinding procedure is complete.
The grinding time should not exceed 30 seconds. Further grinding will not improve
the pulverization of the grinding material, but heating up will increase considerably.
The appliance is designed for short-time operation. Maximum on-time 1 min,
minimum off-time 10 mins. Increasing the on-time or reducing the off-time can
cause the motor to overheat prematurely, which will in turn cause the appliance to
switch off (see Faults and Troubleshooting). The appliance is fused to protect it in
the case of over-use.
Before the grinding procedure is complete, the drive should be raised completely.
Only then should the On/Off - switch be turned off. The advantage of this method
is that the pulverization tool cleans itself. Do not unsrew the grinding container
until the motor has come to a standstill. Any grinding material that adheres to the
guard ring can be swept off on the guard ring into the grinding container with a
cleaning brush (no wire brushes!).
Always remove any grinding scrap which gets into the interstice before using the
appliance again (see ”Maintenance and Cleaning” section).
Please note: The grinding tools, the grinding container and the rotor shaft may
be hot. Observe the safety instructions.
Exchanging the pulverization tools:
Please note: The edges of the blade are sharp. It should only be handled with
protective gloves. Please observe the safety instructions. Note that when changing
the tool directly after a grinding procedure, the pulverization tools are hot. The mill
must first be allowed to cool off.
Before exchanging the pulverization tools, unplug the power cord.
Rotate the mill drive onto its head and push it into the grinding container with the