
9.STOP AND EMERGENCY STOP B-63943EN/02
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9.2 SHUTTING OFF THE MOTOR POWER
The motor power may be shut off through an IGBT (transistor) or an
electromechanical scheme that controls mechanical contacts. When
an α or αi series amplifier is used, the motor power is shut off by an
IGBT (transistor) based on the CNC alarm state (or Ladder program).
To shut off the motor power through an electromechanical scheme, a
line contactor must be installed on the power input line in the power
supply module, thereby providing a direct contactor shut-off route.
(See Fig. 9.5 in Section 9.5, "EMERGENCY STOP SIGNAL.")
The power supply module provides MCC control signals (MCCOFF3
and MCCOFF4) for controlling the contactor. However, these
signals are enabled only when the motor power to all servo and
spindle amplifiers connected to the power supply module is shut off
through the IGBT.
Example 1)
When the *ESP signal is input to the power supply module
The motor power to both servo and spindle amplifiers is shut off
by the IGBT, after which MCC control signals are output.
Example 2)
When a servo alarm occurs
The motor power to the servo amplifier is shut off by the IGBT.
When the spindle works without any trouble, however, the
spindle can be controlled independently and the motor power to
the spindle amplifier is not shut off by the IGBT. In this case,
MCC control signals are not output. When a spindle emergency
stop signal is input using the Ladder program, the spindle motor
is decelerated to a stop. Then, the motor power is shut off
through the IGBT, MCC control signals are output, and the
motor power is shut off electromechanically.
A failure in the amplifier may disable MCC control signals. To
ensure motor power shut-off, therefore, a circuit must be designed in a
redundancy configuration having a route that is independent of the
shut-off function of the amplifier.