GE Industrial Solutions AF-650 GP DeviceNet - Manual (Page 10)

2.1.6 Earth Connection
It is important that all stations connected to the DeviceNet network are con-
nected to the same earth potential. The earth connection must have a low
HF (high frequency) impedance. This can be achieved by connecting a large
surface area of the cabinet to ground, for example by mounting the frequency
converter on a conductive rear plate.
NB!
Particularly when there are long distances between the stations in a Devi-
ceNet network, it may be necessary to use additional potential equalizing
cables, connecting the individual stations to the same earth potential.
Pin no. Terminal Colour Name
1 V- Black GND
2 CAN_L Blue CAN LOW
3 Drain (bare) Screen
4 CAN_H White CAN HIGH
5 V+ Red +24 V
2.1.7 DeviceNet Connection
It is essential to terminate the bus line properly. A mismatch of impedance
may result in reflections on the line that will corrupt data transmission. The
DeviceNet option module is provided with a plug-cable connector. When a
plug connector is used as a splice between two trunk lines, the removal of
devices will not sever the network.
NB!
Install wires only when the network is inactive. This will prevent problems
such as shorting the network supply or disrupting communications.
2.1.8 DeviceNet Termination
Termination resistors should be installed at each end of the bus line. The re-
sistors must be mounted between terminal 2 (CAN_L) and terminal 4 (CAN_H)
and should have the following specification:
121 Ohm, 1 % Metal film, 1/4 Watt
2.1.9 Drop Cable
An alternative to splicing two trunk lines in the connector on the control card
is to use a DeviceNet connection box or a T-connector.
AF-600FP /650 GP DeviceNet Operating Instructions
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