Mitsubishi MELSEC FX3U Series Handbook page 4

[DESIGN PRECAUTIONS]
CAUTION
● When an inductive load such as a lamp, heater, or solenoid valve is controlled, a large current
(approximately ten times greater than normal) may flow when the output is turned from off to on. Take
proper measures so that the flowing current dose not exceed the value corresponding to the
maximum load specification of the resistance load.
● After the CPU module is powered on or is reset, the time taken to enter the RUN status varies
depending on the system configuration, parameter settings, and/or program size.
Design circuits so that the entire system will always operate safely, regardless of this variation in time.
● Simultaneously turn on and off the power supplies of the CPU module and extension modules.
● If a long-time power failure or an abnormal voltage drop occurs, the PLC stops, and output is turned
off. When the power supply is restored, it will automatically restart (when the RUN/STOP/RESET
switch is on the RUN side).
[INSTALLATION PRECAUTIONS]
WARNING
● Make sure to cut off all phases of the power supply externally before attempting installation or wiring
work. Failure to do so may cause electric shock or damage to the product.
● Use the product within the generic environment specifications described in the User's Manual
(Hardware) for the CPU module to be used.
Never use the product in areas with excessive dust, oily smoke, conductive dusts, corrosive gas (salt
air, Cl , H S, SO
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condensation, or rain and wind.
If the product is used in such conditions, electric shock, fire, malfunctions, deterioration or damage
may occur.
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or NO ), flammable gas, vibration or impacts, or expose it to high temperature,
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