Topology examples

Feed-in if the bus cable is long

If the distance between the bus master and the slaves is longer, it may be necessary to feed in 24 V DC for the FieldBusPlugs on a second place. Check with: “Supply Calculation” scheme.

Feed-in, if the bus cable is long

Note

Important: As the S500-FBP remote I/Os are also powered through the FieldbusPlug, the power supply of each cabinet has to be provided locally to avoid too important power loss.

In the same way, when the distance between slaves or cabinets are quite important, it is always better to provide the power supply locally. Use the PDV12 Feed-in accessory to connect a new power supply. Also follow carefully the earthing/grounding and potential equalization rules (see the dedicated chapter further away).

Topology, if also other PROFIBUSâ slaves are connected

Topology, if only one or few FBP slaves are connected

Topology, if only one FBP slave distant from the bus master is connected

Topologies with Repeater

Repeater at the end of segment 1 and at the beginning of the segment 2

Note

• Repeaters have to be calculated as physical stations also within the max. number 32 stations per segment. Thus only 30 slaves can be connected to a segment.
• Each segment can have the allowed bus length referring to Technical Data PROFIBUSâ DP built with PDP21 and PDP22 FieldBusPlugs “”.
• Set baud rate on the repeater carefully according to the manufacturer’s instruction.
• Most of the repeaters do not support baud rates up to 12 Mbit/s.
• Regard termination carefully. Repeaters normally have built in termination that can be switched on. Consult manufacture’s instruction.
• Do not use more repeaters than necessary. Repeaters decrease the stability of the whole field bus system and make it more sensitive for electromagnetic influence.
• Keep unshielded cores as short as possible.
• Take care for perfect grounding of the shields.

Notes: