![SEW-Eurodrive DHF41B Manual Download Page 12](http://html.mh-extra.com/html/sew-eurodrive/dhf41b/dhf41b_manual_1250085012.webp)
12
Manual – MOVI-PLC® advanced DHF41B DeviceNet and PROFIBUS DP-V1 Fieldbus Interfaces
4
Shielding and routing bus cables
Assembly and Installation Notes on the DeviceNet Fieldbus
Make the connection according to the color code specified in the following table.
Connecting
DHF41B to the
DeviceNet
According to the DeviceNet specification, a linear bus structure without or with very short
droplines is required.
The maximum permitted cable length depends on the baud rate setting:
4.3
Shielding and routing bus cables
The DeviceNet interface supports RS-485 communications protocol and requires cable
type A specified for DeviceNet in accordance with EN 50170 as shielded, twisted-pair
cable for the physical connection.
Correct shielding of the bus cable attenuates electrical interference that can occur in
industrial environments. The following measures ensure the best possible shielding:
• Manually tighten the mounting screws on the connectors, modules, and equipotential
bonding conductors.
• Apply the shielding of the bus cable on both ends over a large area.
• Route signal and bus cables in separate cable ducts. Do not route them parallel to
power cables (motor leads).
• Use metallic, grounded cable racks in industrial environments.
• Route the signal cable and the corresponding equipotential bonding close to each
other using the shortest possible route.
• Avoid using plug connectors to extend bus cables.
• Route the bus cables closely along existing grounding surfaces.
4.4
Bus termination
In order to avoid disruptions in the bus system due to reflections, each DeviceNet
segment must be terminated with 120-ohm bus terminating resistors at the first and last
physical station. Connect the bus terminating resistor between connections 2 and 4 of
the bus plug.
Pin no.
Signal
Meaning
Color coding
1
V-
0V24
BK
2
CAN_L
CAN_L
BU
3
DRAIN
DRAIN
blank
4
CAN_H
CAN_H
WH
5
V+
24 V
RD
Baud rate
Maximum cable length
500 kBd
100 m
250 kBaud
250 m
125 kBd
500 m
CAUTION
In case of fluctuations in the ground potential, a compensating current may flow via the
bilaterally connected shield that is also connected to the protective earth (PE). Make
sure you supply adequate equipotential bonding in accordance with relevant VDE
regulations in such a case.
Summary of Contents for DHF41B
Page 2: ...SEW EURODRIVE Driving the world ...
Page 123: ...SEW EURODRIVE Driving the world ...