Sequential Muting - Mitsubishi Electric MELSEC-QS Series Safety Application Manual

5
SAFETY APPLICATION CONFIGURATION EXAMPLE (USING A
SINGLE SAFETY PROGRAMMABLE CONTROLLER)
5.6.7

Sequential muting

(1) Application overview
This function temporarily invalidates a shading detection signal such as a light curtain.
This function allows carrying members into a hazardous area without de-energizing a
robot.
The muting is controlled with a muting sensor.
This section explains a sequential muting with four muting sensors.
Start and stop of the robot is controlled with contactors that close and open the power
supply.
Connect the light curtain and contactors to a safety programmable controller.
The safety programmable controller turns on/off the main contacts of the contactors
with sequence program.
When the safety programmable controller detects an error by self-diagnostics, outputs
to the contactors turn off independent of the sequence program.
In this case, the outputs remain off until the safety CPU module or CC-Link Safety
remote I/O module is reset independent of the sequence program.
Configure the sequence program so that the following functions can be achieved.
1) After completing the previous process, allow the muting and then start
carrying members in the hazardous area.
This section shows an example when a start of carry is detected with
sensors.
2) The muting is enabled when the four muting sensors detected works in
correct timing and order while the muting is set to be allowed.
The robot is de-energized when detected timing or order is incorrect.
For the correct timing and order, and conditions to start and end the
muting, refer to the QSCPU Programming Manual (Safety FB).
Once muting has been started, the second muting operation will be
disabled.
3) Set valid period of muting.
If the muting does not end within the set period, it is forcibly terminated
and the robot is de-energized.
4) A muting lamp is on during the muting so that muting status can be easily
recognized.
If an error such as disconnection occurs due to faulty wiring to a muting
lamp during muting, the muting is suspended.
5) When the main contacts of the contactors are welded, do not start the
robot. Input the auxiliary contacts (normally closed contacts) to the safety
programmable controller to check for welding.
6) When an error is detected in the safety remote I/O station on CC-Link
Safety after operation, outputs to the contactors turn off.
5.6 Case Examples
5.6.7 Sequential muting
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