Mitsubishi MELSEC-A A1SJ71PB93D User Manual page 4

[WIRING PRECAUTIONS]
Switch all phases of the external power supply of the PLC system off before
connecting the PROFIBUS cable. If you not switch off the external power
supply, it will cause failure or malfunction of the module.
Be careful not to let foreign matter such as filings or wire chips get inside the
module. These can cause fire, breakdowns and malfunctioning.
The PROFIBUS cable which is connected to the module must be protected
with a duct or secured in position with clamps.
Unless the cable is thus protected or secured, the module or the cable could
be damaged when the cable swings, moves or it is strained with careless
pulls, or it could cause malfunction when the cable contacts with any
undesirable objects.
When disconnecting the PROFIBUS cable from the module, do not pull by
holding the cable section. To disconnect the cable, make sure to hold the
connector which is coupled with the module. Do not attempt to pull the cable
to disconnect it from the module. It could damage the module or the cable, or
cause malfunction due to a poor contact of the cable.
[STARTING AND MAINTENANCE PRECAUTIONS]
Before cleaning, be sure to shut off all phases of the external power supply
used by the system.
Failure to do so may cause electrical shocks.
CAUTION
WARNING
A-3