24VAC via Cat6

Forums › Home Workshop DIY › 24VAC via Cat6

1 | 2

Paul1977

5039 posts

Uber Geek

#2574043 25-Sep-2020 09:38

richms:

If you split the pairs and put DC on it, then that will be across any magnetics that the cable is plugged into and ruin them, whereas there is no DC path between pairs so plugging one in when wired on entire pairs will not cause any current flow thru the device that you mis-connect.

@richms are you talking about if I had an RJ45 on the end and mistakenly plugged it into a network device?

richms

28168 posts

Uber Geek

Trusted

Lifetime subscriber

#2574136 25-Sep-2020 11:49

Paul1977:

richms:

If you split the pairs and put DC on it, then that will be across any magnetics that the cable is plugged into and ruin them, whereas there is no DC path between pairs so plugging one in when wired on entire pairs will not cause any current flow thru the device that you mis-connect.

@richms are you talking about if I had an RJ45 on the end and mistakenly plugged it into a network device?

Yes, basically DC or low frequency AC across a pair will toast anything that you plug in. If its a POE device then worst case you will power it when between pairs like that, or short the supply if its a device that grounds out the unused pairs (not something they should do but many things do)

Richard rich.ms

Paul1977

5039 posts

Uber Geek

#2574170 25-Sep-2020 12:26

richms:

Yes, basically DC or low frequency AC across a pair will toast anything that you plug in. If its a POE device then worst case you will power it when between pairs like that, or short the supply if its a device that grounds out the unused pairs (not something they should do but many things do)

Not an issue in my case then. No RJ45 going on the end, and I can make sure it's labelled. Thanks.

EDIT: If some future owner ignores the label, untwists all the wires, crimps on an RJ45, then plugs in a device (all without checking the other end) - then they deserve to fry their device!

1 | 2