Power Supply Of The Valve Unit And The Bus Couplers; Earthing Of The Valve Unit And Shielding Connection - Aventics VDS-CompactDesign Bedienungsanleitung

VDS-CompactDesign
PROFIBUS DP
5

Power Supply of the Valve Unit and the Bus couplers

The valve unit should be driven using two separate
power supplies. One supplies the power section
(valves), the other supplies the interface and the
electronics. This makes it possible for the valves to
be switched off in an EMERGENCY-OFF situation
whilst maintaining power to the PLC and serial in-
terface (electronics, valve unit and sensors). If the
electronics were to be switched off during opera-
tion the PLC would close down (STOP).
6

Earthing of the Valve Unit and Shielding Connection

The pneumatic units of the various branches and the Bus module must have secure elec-
trical connections both to one another and to earth (PE). This is effected by means of an
assembly plate. An inadequate earth connection can lead to transmission errors where
there is electrical interference and malfunctioning of the unit. Perfect contact with the
mounting plate must be ensured during assembly by the use of serrated lock washers.
The shielding of the data cable is earthened by means of the Siemens Bus terminal in the
control cabinet of the PLC.
The shielding of the data cable and the earth are connected to the valve unit via the main
housing of the plug.
The first and the last contact bridge of valve units with sensor inputs must be connected to
earth (factory made).
AVENTICS | C-Design | 8858903033-BAL-001-AE
24 VDC Valves
PIN 3
PIN 2
24 VDC
Electronics
PE
Fig. 5 Supply Voltage
PIN 1
0 V
27/40