Connecting The Power Supply To A B&R Device; Grounding Concept - Functional Ground - B&R Automation PC 3100 User Manual

5.2.2 Connecting the power supply to a B&R device
Danger!
The entire power supply to the B&R device must be interrupted. Before connecting the power cable, it
must be checked whether it has been disconnected from the voltage source (e.g. power supply unit).
1. Carry out electrostatic discharge on the housing or at the ground connection.
2. Connect the power supply connector to the B&R device and tighten the mounting screws (max. tightening
torque 0.5 Nm).

5.2.3 Grounding concept - Functional ground

Functional ground is a current path of low impedance between circuits and ground. It is used to improve immunity
to interference, for example, and not as a protective measure. It serves only to divert interference, not to protect
against contact with persons.
The device is equipped with 2 functional ground connections:
• Functional ground connection of the power supply
• Ground connection
The following points must be observed to ensure that electrical interference is safely diverted:
• Connect the device to the central grounding point (e.g. the control cabinet or the system) using the shortest
possible low-resistance path.
• Cable design with at least 2.5 mm² per connection. If a cable with wire end sleeve is used with terminal
block 0TB103.9 or 0TB103.91, a cable with a maximum of 1.5 mm² per connection is possible.
• Observe the shielding concept of the conductors. All data cables connected to the device must be shielded.
The functional ground on the B&R device is marked with the following symbol:
1
Ground connection
a At least 1.5 mm²
Automation PC 3100 User's manual V 2.10
Figure 4: Connecting the power supply connector to a B&R device
Power supply connection +24 VDC pin 2
2
b At least 2.5 mm²
Legend
Installation and wiring
3 Central grounding point
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