The following paragraph is from the AB ethernet cable selection guideline:
Shields help to reduce noise coupled to the balanced cables by providing a faraday shield
around the conductors. However this is countered in some cable designs by using poorly
balanced cable pairs. Shields can carry ground currents due to ground offsets with in the
building grounding system. These currents at worse case can cause equipment damage.
At the least, the currents can be disruptive to the network communications. EtherNet/IP
reduces the chance of ground loops by isolating the shield at one end of the channel from
ground. This is done through the use of an RC between the shield and local node ground
connection. The RC is always in the device end and not at the switch end. The switch end
of a shielded channel is always grounded if the switch is grounded.
Can someone tell me what the RC is? There is no definition in the document.
Thanks very much,
Rob
Shields help to reduce noise coupled to the balanced cables by providing a faraday shield
around the conductors. However this is countered in some cable designs by using poorly
balanced cable pairs. Shields can carry ground currents due to ground offsets with in the
building grounding system. These currents at worse case can cause equipment damage.
At the least, the currents can be disruptive to the network communications. EtherNet/IP
reduces the chance of ground loops by isolating the shield at one end of the channel from
ground. This is done through the use of an RC between the shield and local node ground
connection. The RC is always in the device end and not at the switch end. The switch end
of a shielded channel is always grounded if the switch is grounded.
Can someone tell me what the RC is? There is no definition in the document.
Thanks very much,
Rob
