Cable and shielding

Shielded twisted-pair cables (2x2) with a characteristic impedance of between 108 and 132 ohm is recommended for the CAN wiring. If the CAN transceiver’s reference potential (CAN ground) is not to be connected, the second pair of conductors can be omitted. (This is only recommended for networks of small physical size with a common power supply for all the devices).

ZB5100 CAN Cable

A high quality CAN cable with the following properties is included in BECKHOFF's range:

• 2 x 2 x 0.25 mm² (AWG 24) twisted pairs, cable colors: red/black + white/black
• double shielded
• shield braid with filler strand (can be attached directly to pin 3 of the 5-pin connection terminal),
• flexible (minimum bending radius 35 mm when bent once, 70 mm for repeated bending)
• characteristic impedance (60 MHz): 120 ohm
• conductor resistance < 80 ohm/km
• sheath: gray PVC, outer diameter 7.3 +/- 0.4 mm
• weight: 64 kg/km.
• printed with "Beckhoff ZB5100 CAN-BUS 2x2x0.25" and meter marking (length data every 20 cm)

ZB5200 CAN/DeviceNet Cable

The ZB5200 cable material corresponds to the DeviceNet specification, and is also suitable for CANopen systems. The ready-made ZK1052-xxxx-xxxx bus cables for the fieldbus box modules are made from this cable material. It has the following specification:

• 2 x 2 x 0.34 mm² (AWG 22) twisted pairs
• double shielded · shield braid with filler strand
• characteristic impedance (1 MHz): 126 ohm
• conductor resistance 54 ohm/km
• sheath: gray PVC, outer diameter 7.3 mm
• printed with "InterlinkBT DeviceNet Type 572" as well as UL and CSA ratings
• stranded wire colors correspond to the DeviceNet specification
• UL recognized AWM Type 2476 rating
• CSA AWM I/II A/B 80°C 300V FT1
• corresponds to the DeviceNet "Thin Cable" specification

Shielding

The shield is to be connected over the entire length of the bus cable, and only galvanically grounded at one point, in order to avoid ground loops.
The design of the shielding, in which HF interference is diverted through R/C elements to the mounting rail assumes that the rail is appropriately grounded and free from interference. If this is not the case, it is possible that HF interference will be transmitted from the mounting rail to the shield of the bus cable. In that case the shield should not be attached to the couplers - it should nevertheless still be fully connected through.

Cable colors

Recommended application of Beckhoff CAN cables: