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[INSTALLATION PRECAUTIONS]
CAUTION
Use the MELSEC-ST system in the general environment specified in the MELSEC-ST system users
manual. Using this MELSEC-ST system in an environment outside the range of the general
specifications could result in electric shock, fire, erroneous operation, and damage to or deterioration
of the product.
Mount the head module and base module(s) on the DIN rail securely (one by one) referring to the
MELSEC-ST system users manual and then fix them with stoppers. Incorrect mounting may result in
a fall of the module, short circuits or malfunctions.
Secure the module with several stoppers when using it in an environment of frequent vibration.
Tighten the screws of the stoppers within the specified torque range. Undertightening can cause a
drop, short circuit or malfunction. Overtightening can cause a drop, short circuit or malfunction due to
damage to the screw or module.
Make sure to externally shut off all phases of the power supply for the whole system before mounting
or removing a module. Failure to do so may damage the module.
(1) Online replacement of the power distribution module and/or the base module is not available.
When replacing either of the modules, shut off all phases of the external power supply.
Failure to do so may result in damage to all devices of the MELSEC-ST system.
(2) The I/O modules and the intelligent function modules can be replaced online.Since online
replacement procedures differ depending on the module type, be sure to make replacement as
instructed.
For details, refer to the chapter of online module change in this manual.
Do not directly touch the module's conductive parts or electronic components. Doing so may cause
malfunctions or failure of the module.
Make sure to securely connect each cable connector. Failure to do so may cause malfunctions due
to poor contact.
DIN rail must be conductive; make sure to ground it prior to use. Failure to do so may cause electric
shocks or malfunctions. Undertightening can cause a short circuit or malfunction. Overtightening can
cause a short circuit due to damage to the screw.
