Mitsubishi Electric Melsec-Q172DCPU User Manual page 138

3 DESIGN
Do not touch the heat radiating fins of controller or servo amplifier, regenerative resistor and
servo motor, etc. while the power is ON and for a short time after the power is turned OFF. In this
timing, these parts become very hot and may lead to burns.
Always turn the power OFF before touching the servo motor shaft or coupled machines, as these
parts may lead to injuries.
Do not go near the machine during test operations or during operations such as teaching.
Doing so may lead to injuries.
Always mount a leakage breaker on the Motion controller and servo amplifier power source.
If mounting of an electromagnetic contactor for power shut off during an error, etc., is specified in
the instruction manual for the servo amplifier, etc., always mount the electromagnetic contactor.
Mount an emergency stop circuit externally so that the operation can be stopped immediately and
the power shut off.
Use the Motion controller, servo amplifier, servo motor and regenerative resistor with the correct
combinations listed in the instruction manual. Other combinations may lead to fire or faults.
If safety standards (ex., robot safety rules, etc.,) apply to the system using the Motion controller,
servo amplifier and servo motor, make sure that the safety standards are satisfied.
Construct a safety circuit externally of the Motion controller or servo amplifier if the abnormal
operation of the Motion controller or servo amplifier differ from the safety directive operation in
the system.
In systems where coasting of the servo motor will be a problem during the forced stop, the
emergency stop, servo OFF or when the power is shut OFF, use dynamic brakes.
Make sure that the system considers the coasting amount even when using dynamic brakes.
In systems where perpendicular shaft dropping may be a problem during the forced stop, the
emergency stop, servo OFF or when the power is shut OFF, use both dynamic brakes and
electromagnetic brakes.
The dynamic brakes must be used only during the forced stop, the emergency stop and errors
where servo OFF occurs. These brakes must not be used for normal braking.
The brakes (electromagnetic brakes) assembled into the servo motor are for holding applications,
and must not be used for normal braking.
The system must have a mechanical allowance so that the machine itself can stop even if the
stroke limits switch is passed through at the max. speed.
Use wires and cables that have a wire diameter, heat resistance and bending resistance
compatible with the system.
Use wires and cables within the length of the range described in the instruction manual.
The ratings and characteristics of the parts (other than Motion controller, servo amplifier, servo
motor) used in a system must be compatible with the Motion controller, servo amplifier and servo
motor.
Install a cover on the shaft so that the rotary parts of the servo motor are not touched during
operation.
There may be some cases where holding by the electromagnetic brakes is not possible due to
the life or mechanical structure (when the ball screw and servo motor are connected with a
timing belt, etc.). Mount a stopping device to ensure safety on the machine side.
CAUTION
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