sequence shall be:
a) cut power to all machine actuators and any sockets (if
provided) except workpiece clamping (if fitted) and
actuate the brake;
b) cut power to brake (if electrical brake is fitted) after the
saw spindle has come to rest, e.g. by using a time
delay in accordance with 5.2.1.2 b).
If a time delay device is used the time delay shall conform
to 5.2.1.2 b) and shall be at least the maximum run-down
time. Either the time delay shall be fixed or the time delay
adjustment device shall be sealed.
The safety related part of the control systems (also see
5.2.1) for the emergency stop shall be at least PL=c in
accordance with the requirements of EN ISO 13849-
1:2008.
Verification: By checking relevant drawings and/or circuit
diagrams, inspection of the machine and relevant
functional testing of the machine.
Where a circular saw bench is designed to operate at
more than one main saw blade/milling tool speed, the
following conditions shall be met:
The selected speed shall be visible or indicated at the
operator's position.
On circular saw benches with varying the main saw blade
speed by changing the belts on the pulleys the control
system for indication of the main saw blade speed shall at
least conform to PL=b in accordance with the
requirements of EN ISO 13849-1:2008.
On circular saw bench fitted with an incremental speed
change motor, e.g. a change pole motor, the speed shall
at least be selected in PL=c in accordance with the
requirements of EN ISO 13849-1:2008 and be indicated in
rpm at the control.
On circular saw bench fitted with an automatic control
device for infinitely varying the speed (e.g. a frequency
inverter) for the main saw blade the device shall be such
that the actual speed shall not exceed the selected speed
by more than 10 %. The selected speed shall be indicated
prior to main saw blade start at the control. The safety
related part of the control system for speed control shall
be PL=c in accordance with the requirements of EN ISO
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