Grounding principles

The PROFIBUSâ FieldBusPlug cable as well as the standard PROFIBUSâ cable is equipped with a perfect shield: aluminium coated foil and a braided shield.

Regarding EMC, laboratory measurements have proved that grounding is not necessary when the PROFIBUSâ DP is built up with PDP21 / PDP22 only, normal industrial environment supposed.

According to IEC60204 / EN60204 (chapter 6.3.3) all metallic parts must be grounded to avoid that they - in case of an insulation fault, unexpected and unobserved - are connected to a dangerous voltage.

It is highly recommended to connect the shield to ground:

• at the PROFIBUSâ DP master and
• when entering / leaving a cabinet and
• every third or forth FieldBusPlug and
• when connecting other - non FieldBusPlug slaves - in accordance with the manufacturer’s instruction.