Grounding Concept Functional Ground - B&R Industries MAPPC900-ENG User Manual

Installation • Connecting to the power mains

2.4 Grounding concept functional ground

Functional ground is a current path of low impedance between electrical circuits and ground. It is used, for example,
to improve immunity to disturbances and not necessarily as a protective measure. It therefore serves only to deflect
disturbances, not to provide any kind of protection against electric shock.
The functional ground on the device has 2 connections:
• Supply voltage
• Ground connection
To guarantee safe conductance of electric disturbances, the following points should be observed:
• The device should be connected to the central grounding point in the control cabinet using the shortest
route possible.
• A cable with a minimum cross section of 2.5 mm² per connection should be used. If a cable with wire end
sleeves is connected to the 0TB103.9 or 0TB103.91 terminal block, then a cable with maximum 1.5 mm²
per connection is possible.
• Note the line shielding concept; all connected data cables are used as shielded lines.
Functional ground is indicated on the B&R device with the following symbol:
Supply voltage
Ground connection
158
Figure 95: Panel PC 900 - Grounding concept
Control cabinet
Grounding strip
1.5 mm²
1.5 mm²
Panel PC 900 User's Manual V1.05