GE Industrial Solutions OKCV3000CN DeviceNet - Manual (Page 53)

DeviceNet
APPENDIX D
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CABLE AND POWER CONSIDERATIONS
Type of connection
DeviceNet has a linear topology. There are two type of connection of DeviceNet:
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through Trunk line, that is the main line of the network;
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through Drop line, that is small line derived from the trunk. There may be more than one drop line in the
same network. One or more nodes can be attached to this drop line.
Type of cable
DeviceNet cable consists of two shielded twisted pairs on a common axis with a ground wire in the center
covered with an overall braid shield.
There are two type of DeviceNet cable:
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Thick Cable is commonly used as Trunk line when length is important.
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Thin Cable is smaller and more flexible than Thick Cable. It is commonly used for drop lines, but can also
be used, for shorter distances, as trunk line.
Terminating resistor
DeviceNet requires a terminating resistor to be installed at each end of the trunk. The resistor requirements are:
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121 ohm
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1% Metal Film
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1/4 Watt
Terminating resistors should not be installed at the end of a drop line, only at the two ends of
trunk line.
Terminating resistor must connect CAN_L and CANH signals
DeviceNet Connector
The following table illustrates wire colors and pin-out of the screw connector for DeviceNet.
IMPORTANT:
IMPORTANT
Connector Connector Designator Wire Color
1 V- black
2 CAN L blue
3 Drain bare
4 CAN I-I white
5 red
TNetl5O
DeviceTap
Device taps provide points of attachment onto the trunk line. Devices can be connected to the network either
directly to the tap or with a drop line. Taps also provide easy removal of a device without disrupting network
operation.
L1
APPENDIX D