Siemens SINUMERIK MCU1720, Equipment Manual

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Connecting
8
8.1 Notes on connecting
WARNING
Risk of fire and electric shock
The on/off switch does not isolate the device from the power supply. Risk of electric shock if
the device is opened incorrectly or defective. There is also a risk of fire if the device or
connecting cables are damaged.
You should therefore protect yourself and the device as follows:
● Always pull out the power plug when you are not using the device or if the device is
defective. The power plug must be freely accessible.
● Connect the device to a protective conductor as instructed, see section "Connecting the
protective conductor".
● Use a central isolating switch for cabinet installation.
WARNING
Risk of lightning strikes
A lightning flash may enter the mains cables and data transmission cables and jump to a
person.
Death, serious injury and burns can be caused by lightning.
Take the following precautions:
● Disconnect the device from the power supply in good time when a thunderstorm is
approaching.
● Do not touch mains cables and data transmission cables during a thunderstorm.
● Keep a sufficient distance from electric cables, distributors, systems, etc.
NOTICE
Fault caused by I/O devices
The connection of I/O devices can cause faults in the device.
The result may be personal injury and damage to the machine or plant.
Note the following when connecting I/O devices:
● Read the documentation of the I/O devices. Follow all instructions in the documentation.
● Only connect I/O devices that are suitable for industrial applications in accordance with
EN 61800-3 and IEC 61800-3.
● I/O devices that are not hotplug-capable may only be connected after the device has been
disconnected from the power supply.
MCU 1720
Equipment Manual, 09/2019, A5E47437728B AB
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