Power Supply Built-In Unit; Connecting The Protective Earth - Siemens SIMATIC IPC477E Operating Instructions Manual

3.3.2

Power supply built-in unit

3.3.2.1

Connecting the protective earth

A connected protective conductor conducts dangerous electrical charges away from the
metal enclosure. The current flowing through the protective conductor when such a fault
occurs triggers a primary fuse that disconnects the device from the power supply.
The protective conductor also improves the discharge of interference generated by external
power cables, signal cables or cables for I/O devices to ground.
The connection for the protective conductor is labeled with the following symbol:
Electric shock and risk of fire
High voltage may be present in a defective device, which can cause fire or an electric
shock if touched. Death and serious bodily injury can result.
• Connect the device to the protective conductor before you put it into operation.
• The protective conductor connection on the device must be connected to the protective
• Never operate the device without protective conductor.
• If a device is defective, decommission it without delay and mark it accordingly.
Requirement
● The device is installed
● 1 protective conductor with minimum core cross-section of 2.5 mm
● 1 T20 screwdriver
● 1 cable lug for M4
SIMATIC IPC477E
Operating Instructions, 12/2016, A5E37455003-AB
WARNING
conductor of the control cabinet or system in which the device is installed.
Mounting and connecting the device
3.3 Connecting the device
2
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