Motor protection
© ALTENDORF 2007
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7.8
Motor protection
If the motor protection cuts in it is a sign that the mo-
tor is being overloaded and the cause must be iden-
tified and rectified before the machine is switched
back on (e.g. blocking of the drive by a jammed
workpiece, feed too great or failure of a mains
phase)
The drive motors are protected against overload by
a coil protection. If the motor gets too hot this auto-
matically switches the motor off. Note here that for
machines with scorers this drive is switched off as
well, even if this motor was not overloaded. The
machine cannot be switched back on until the mo-
tor has cooled down. The motor can take several
minutes (max. 10 minutes) to cool down!
Rapid flashing (frequency 4Hz) of the main saw ON
button signals that the motor protection has cut in.
Checking the winding protection
The resistance figure (750 Ohm ± 200 Ohm) of the
PTC resistors is to be checked at least once a year
in the motor terminal box by a specialist electrician.
The test voltage of the meter may not exceed 1.5V
for this test!
