User`s manual

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3 DESIGN
3.2.2 Safety circuit design
(1) Concept of safety circuits
When the Multiple CPU system is powered on and off, normal control output may
not be done momentarily due to a delay or a startup time difference between the
Multiple CPU system power supply and the external power supply (DC in
particular) for the control target.
Also, an abnormal operation may be performed if an external power supply fault
or Motion controller failure takes place.
To prevent any of these abnormal operations from leading to the abnormal
operation of the whole system and in a fail-safe viewpoint, areas which can result
in machine breakdown and accidents due to abnormal operations
(e.g. emergency stop, protective and interlock circuits) should be constructed
outside the Multiple CPU system.
(2) Emergency stop circuit
The circuit should be constructed outside of the Multiple CPU system or servo
amplifier. Shut off the power supply to the external servo amplifier by this circuit,
make the electromagnetic brakes of the servomotor operated.
(3) Forced stop circuit
(a) The forced stop of all servo amplifiers is possible in a lump by using the EMI
forced stop input of Motion CPU modules. After forced stop, the forced stop
factor is removed and the forced stop canceled.
(The servo error detection signal does not turn on with the forced stop.)
The EMI forced stop input cannot be invalidated in the parameter setting of
system setting.
Make the forced stop input cable within 30m(98.43ft.).
The wiring example for the EMI forced stop input of Motion CPU module is
shown below.
(Note): The EMI forced stop input can be invalidated in the system
settings.
(Note-1): Both of positive common and negative common can be used.
QnUD(H)
CPU
EMI
EMI.COM
Q61P
<Motion CPU module>
Q17 D
CPU
R
Forced stop
EMI.COM
24VDC
EMI
(Note-1)
Forced stop
24VDC
R