Nortech Systems Adept RS-232/TERM - Manual (Page 121)

DeviceNet Physical Layer and Media
Adept SmartController User’s Guide, Rev. E 121
DeviceNet Connectors
DeviceNet allows different connectors, which may be grouped into open and sealed
connectors. The open connectors are available with screw or with crimp connectors. The
sealed connectors are available in mini-style and micro-style sizes. See
Figure B-4 and
Table B-4 for more details.
Figure B-4. DeviceNet Connectors
Termination of the DeviceNet Network
The DeviceNet network uses the Controller Area network (CAN) bus as the physical
layer. This requires that the trunk line of your DeviceNet network be terminated with a
resistor at each end. This terminates the signal lines.
The terminating resistor:
• Prevents reflection of communication signals on the network.
• Connects the two signal conductors.
• Must be sealed if the end node uses a sealed tee.
• Must be open if the end node uses an open-style tap.
When using the open-style terminating resistor, connect a 121ohms, 1/4W resistor to
CAN_H and CAN_L (between blue and white data-pair wires).
NOTE: A terminating resistor must also be used whenever a short drop
line exceeds 6m (20 ft.).
Table B-4. DeviceNet Connector Styles
Connector Description
Open plugable Uses screws to attach cable wires to a removable
connector
Open hard-wire Uses wires attached directly to screw terminals
Sealed mini-style Attaches to taps and thick or thin cable
Sealed style micro Attaches to thin cable only – has a reduced
current rating
Unsealed
Screw
Connector
Unsealed
Hard Wired
Sealed
Mini-Style Sealed
Micro-Style
Connector