Specifications

Replacing the TO BE CARRIED OUT BY QUALIFIED PERSONNEL ONLY.
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(i) Open the lid, disconnect the power supply and remove the rotor assembly.
Remove the bowl as described earlier, (see page 16).
(ii) Pinch the top section of the rubber motor gaiter and pull up and over the
plastic moulding.
NB - Do not pull the gaiter up more than is necessary to gain access with a
'Posidrive' screwdriver as shown in Fig. 15A.
(iii) Viewing around the side of the motor, the heads of the three clamping
screws securing the motor assembly to the base moulding are clearly
visible. Unscrew each one by approximately 5 turns and use the end of the
screwdriver to swivel the damp plate through 90°.
(iv) Note the orientation of the motor assembly and then tilt to one side and lift
out through the hole.
It is not necessary to unplug the main harness or to disconnect the earth
lead.
(v) With reference to Fig. 15B, remove the old brushes, noting carefully the
relationship between the components.
The area in the vicinity of the brush housing must be completely cleared
of carbon dust. Use airline or similar to blow area clear.
Fit the new set of brushes, ensuring that they move freely within the carrier
and that the spring is effective. Important: The pigtails of the 120V Mistral
1000 motor brushes must be coiled behind the spring as shown. When
fitting this brush assembly to the motor the pigtail must be located in the
groove of the brush housing, ensuring that the pigtail is not trapped
between the housing and carrier.
(vi) Re-locate the motor assembly in the same orientation as previously noted.
Check that the wiring harness, and in particular the earth lead, is not
trapped under the motor mount plate.
Swivel the damp plates back into position and lightly tighten each damp
screw. Finally tighten each screw to a torque setting of 2.3 Nm (20lb in).
Re-position the motor gaiter and replace the bowl and lid as described
earlier, (see page 16).
(vii) Run the centrifuge with an unloaded rotor (with a full complement of
buckets) for half an hour at 1000 rpm to bed in the brushes.
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