Start-Up/Off Check Function - Mitsubishi Electric MELSEC Q Series User Manual

4
FUNCTIONS
4.2

Start-up/off Check Function

This function is to start the system after making sure that status of the safety relay module
and external device are normal.
When the safety relay and electromagnetic switch are connected, connecting the normally
closed contacts to the start-up/off check terminal of the safety relay module inhibiting the
start-up at a failure such as contact welding.
Non-safety part
4
- 2 4.2 Start-up/off Check Function
Off check
Start-up switch
Start-up
command
Emergency stop
switch
Light curtain,
Safety status
etc.
Figure 4.2 Off check function
POINT
• Connect normally closed contact of forcibly guided type electromagnetic
switch to off check.
• If connecting normally closed contact of electromagnetic switch other
than forcibly guided type, contact separation of the electromagnetic
switch cannot be detected.
• Wire the start-up/off check input so that the external wiring length can be
50m (164.04 feet) or less.
• The timing of safety input and start-up/off check are inconstant.
• Therefore, control using this timing cannot be made.
Safety relay
module
Safety
output
Electromagnetic
switch
Power, etc.