Procentec ProfiHub B5 Plus - Channel Structure; Grounding System

To Next Page

To Previous Page

ProfiHub B5+ / B5+RD User Manual

_______________________________________________

Version 2.0 – July 2014 Page 10 / 56

1.4 Channel Structure

Each Channel is electrically isolated and internally connected to the transparent intelligent backbone.

The termination is switchable and powered by the ProfiHub. The shielding of the PROFIBUS cable can

be directly grounded or indirectly grounded (see the next paragraph).

1.5 Grounding System

The ProfiHub B5+ can be grounded by 3 methods:

1) Direct grounding on the Ground Rail

2) Indirect grounding (through a capacitor)

3) Combination of direct and indirect.

The power supply must be grounded directly on the Ground Rail. The shielding of the PROFIBUS

cables can be directly or indirectly grounded. If you do not want to ground all or some cables to the

common ground, i.e. compensating current, the cable shielding must be connected to pin ‘I’ which

stands for Indirect grounding. A capacitor with a parallel high value resistor will separate the 2

potentials (

Fig. 5

), ensuring protection of the signal against non-DC disturbances.

If by accident on 1 channel the Direct Grounding is connected with the Indirect Grounding, the

connection to the Direct Grounding bypasses the capacitor in the Indirect Ground connection. The

current on the shield will flow to Direct Ground.

Fig. 5 - Channel structure