Beckhoff EP1957-0022 Operating Instructions Manual page 24

Operation
Wiring recommendations
Detailed recommendations for EtherCAT wiring can be found in the documentation "Design
recommendations for EtherCAT/Ethernet infrastructure", which is available for download from
www.Beckhoff.de.
EtherCAT uses four cable wires for signal transmission. Due to automatic cable detection (auto-crossing)
symmetric (1:1) or cross-over cables can be used between EtherCAT devices from BECKHOFF.
5.2.2.4 Power connection and grounding
This chapter provides basic information about the power supply and grounding of the EP1957 TwinSAFE
EtherCAT Box. In particular, please note that the General information on connecting the functional earth only
serves as an example.
Supply voltages (power connection)
The supply and distribution of the supply voltages takes place via the connections:
• Us/Up IN for feeding in the supply voltages
• Us/Up OUT for forwarding the supply voltages.
Both connections have an M8 thread and are located to the left (Us/Up IN) and right (Us/Up OUT) of the
TwinSAFE EtherCAT Box (see figure: EP1957 - power connection).
Information: An overview of pin assignment for the two connections can be found later in this chapter.
General information for connecting the functional earth
The grounding lugs of the EP1957 are internally connected to the safe outputs (pin 5 of the M12
connections).
To provide functional earthing
• have a large surface
• have low resistance and
• be permanent.
In order to establish a permanent connection, all operating states of the machine, such as vibrations, must
be taken into account.
The connection can be established using the following two methods:
1. via a bolted connection from the TwinSAFE EtherCAT Box to the machine bed
2. through a ring terminal (hole dia. 4.3 mm) with cable connection to the functional earth
A grounding lug is available at the upper and lower mounting points (hole dia. 5 mm for M4 thread) on the
housing.
Connecting the functional earth
The functional earth connection should have low resistance and a large surface.
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, if possible the connection should:
NOTE
Version: 2.0.0 EP1957-0022 and EP1957-2222