Bonded Vs. Non-Bonded Twisted Cables

Bonded Cables have (paired) wires molded together usually inside a jacket. Bonded-pair cables maintain a fixed conductor-to-conductor centricity between the twisted pair conductors by physically bonding them together, preventing even temporary separation (Figure 1). This greatly reduces the risk of impedance loss and crosstalk when being curved, bent or folded.

Non-Bonded Cables are separate wires together in a jacket.


Reference:
https://www.digikey.com/en/articles/how-to-ensure-gigabit-ethernet-signal-integrity-in-long-distance-industrial-automation-deployments?utm_campaign=https://www.digikey.com/e&utm_content=digikey&utm_medium=social&utm_source=twitter

How might this impact signal and data transmission in the context of multi stranded pair conductors in household runs of CAT 5/6 for Ethernet?

I also wonder if the turn is tight enough, would there also not be additional loss because now the conductors on either side of the bend could interact as they approach parallel. I could see this scenario for any bends that exceed 90 degs. Which begs the question, if the bend is less than 90 degs then would you actually get the gaps produced in non-bonded pairs? How would any shielding surrounding the pairs be implicated? is this why some ethernet cables include a “plenum”, to help keep bend radius within a tollerable limit to prevent gaps in the twisted pairs? At this point I am wondering under what use cases you would want to use bonded over un bonded cable pairs.

Thanks for bringing up this topic. A bit more context will help me understand when I would want to consider running bonded vs unbonded cable pairs.

It is only now that I am thinking of instances when a twisted pair might run inside a project box or be used as line feeds to and from such box. Very interesting.

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