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5.0 Switch Gear
5.1 The Padlockable Isolator
With this switch in the OFF position the machine is effectively isolated
from the supply to allow personnel safe access for maintenance or
repair work and to prevent dangerous restarts. In order to prevent
unauthorised use of the machine the switch can also be secured in the
OFF position using a padlock.
To operate the machine first turn the isolator to the ON position.
5.2 Start / Stop Buttons
The cutterblock motor is then started by pushing the green (power on) button on the starter
panel, and stopped using the red (power off) button. The mushroom headed lock-off stop
switch, once pressed will remain locked in the off position. To restart the machine it is
necessary to release the off button by twisting it in a clockwise direction.
5.3 Two/Three Position Rotary Switch
The feed rollers are driven via a separate gearbox motor, which is
controlled using the rotary switch below the isolator. A single phase
machine has only two positions: ON and OFF. A three phase machine
has three:
Position 0 – OFF
Position I – Slow Run (4.5m/min)
Position II – Fast Run (7 m/min)
5.4 Circuit Protection
In case of a mains failure the starter is fitted with no volt release protection and will not restart
without being switched on again. The starter is also fitted with an overload protection device.
An electrical overload occurs where an electric motor is subjected to a greater load than it was
designed for. This can be caused by short circuit, by incorrect installation, or by misuse
(including poor machine maintenance). The inbuilt breaker will therefore help prevent damage
to the motor should such a situation occur. The motor cannot be restarted until the breaker has
reset itself.
5.5 Brake Release Switch
Machines fitted with an electro-magnetic brake unit are also equipped with a ‘Brake Release’
switch. This switch makes it possible to release the brake mechanism, allowing the operator to
rotate the cutterblock when changing or adjusting the cutting knives. To operate the switch first
turn the isolator to ON, release the mushroom headed lock off stop switch, and turn the brake
release to ‘BRAKE RELEASE’. It is not possible to start the cutterblock motor with the switch in
this position. To start the cutterblock motor turn the switch back to the
RUN position.
5.6 Optional Emergency Foot Operated Stop Switch
This switch is provided for use in emergency situations only. We do not
recommend that it is used in lieu of the mushroom headed lock-off stop
switch on the front of the starter panel.
