5.11 Safety Function
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5.11
Safety Function
The safety function is incorporated in the multi-winding drive unit to reduce the risk associated with the
machine by protecting workers from injury and by securing safe machine operation. Especially when working
in hazardous areas inside the safeguard, as for machine maintenance, it can be used to avoid adverse machine
movement.
5.11.1
Hard Wire Base Block (HWBB) Function
The Hard Wire Base Block function (hereinafter referred to as HWBB function) is a safety function designed
to baseblock the servomotor (shut off the motor current) by using the hardwired circuits. Each circuit for two
channel input signals blocks the run signal to turn off the power module that controls the motor current, and
the motor current is shut off. (Refer to the diagram below.)
Note: For safety function signal connections, the input signal is the 0 V common and the output signal is the source output.
This is the opposite of other signals described in this manual. To avoid confusion, the ON and OFF status of signals
for safety functions are defined as follows:
ON: The state in which the relay contacts are closed or the transistor is ON and current flows into the signal line.
OFF: The state in which the relay contacts are open or the transistor is OFF and no current flows into the signal line.
CN8
CN8
24-V
power
supply
Fuse
Switch
0 V
Motor
/HWBB1+
/HWBB1-
/HWBB2+
/HWBB2-
SERVOPACK 1
Converter 1
Block
Block
Power supply
Run
signal
4
3
6
5
/HWBB1+
/HWBB1-
/HWBB2+
/HWBB2-
SERVOPACK 2
Converter 2
Control
circuit
Control
circuit
Block
Block
Power supply
Power
module
Power
module
Run
signal
4
3
6
5
