AC500 and AC500-eCo PLC devices are Class II/Class III devices and do not require a Protective Earth (PE) connection.
For proper EMC performance, all metal parts, DIN rails, mounting screws, and cable shield connection terminals are connected to a common ground and provide Functional Earth (FE). This is typically connected to a common reference potential, such as equipotential bonding rails.
Signal Grounds (SGND or GND) are used for signal reference and must not be connected to cable shields, FE or other signals unless otherwise specified in the specific device description.
For the supply of the modules, power supply units according to SELV or PELV specifications must be used.
Safety Extra Low Voltage (SELV) and Protective Extra Low Voltage (PELV)
Safety Extra Low Voltage (SELV) and Protective Extra Low Voltage (PELV)
To ensure electrical safety of AC500/AC500-eCo extra low voltage circuits, 24 V DC supply, communication interfaces, I/O circuits, and all connected devices must be powered from sources meeting requirements of SELV, PELV, class 2, limited voltage or limited power according to applicable standards.
WARNING
Improper installation can lead to death by touching hazardous voltages!
To avoid personal injury, safe separation, double or reinforced insulation and separation of the primary and secondary circuit must be observed and implemented during installation.
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Only use power converters for safety extra-low voltages (SELV) with safe galvanic separation of the primary and secondary circuit.
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Safe separation means that the primary circuit of mains transformers must be separated from the secondary circuit by double or reinforced insulation. The protective extra-low voltage (PELV) offers protection against electric shock.