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I had to move a card reader from one office to another. The old location was a usoc jack punched down on the orange pair. I had to use a 568 B jack. I punched it down on the green pair which I believe is correct. It just seems really strange that they aren't using the middle pair. Any thoughts?

RE: usoc

USOC is an acronym for Universal Service Order Code. In the Bell System days, codes were assigned to all kinds of things to make the system of ordering and installation easier. In relation to jacks and modular jacks, the USOC indicated a specific wiring arrangement with a specific jack hardware to meet that requirement. In today's world everything seems to get misapplied and misused!

So how are YOU defining USOC jack? Middle pair? The term 568B is NOT a USOC, but a TIA/EIA wiring arrangement for an 8-position 8-contact modular jack for Ethernet. Is your card reader an Ethernet device or something else?


RE: usoc

Who's "they" and what do you mean "middle" pair?  A USOC jack is Leviton's term for a 6p6c jack.  Orange to green pair conversion is correct if you're using an 8-pin 568B wired jack.  Since the plug on the card reader is probably 6-pin also, it makes perfect sense to not use the "3&4 middle" pins that a 48 volt phone line would use.  It sometimes saves the reader from an idiot who plugs it into a working phone line smile

USOC style is paired connections from the center of the jack to the outside as in 54 36 27 and 18 form 4 lines.  Subtract 1 for USOC 6-pin jacks.


RE: usoc

This link will show you the USOC standards and pin outs for each. This is all we had before Ethernet used 4 pair as a transport medium.


Here is the "standards" behind 568? It's all about the pin outs.

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RE: usoc

I would not call it "horrible" per se, since it is very limited, but is complete for what is shows, minus history.

***The Wikipedia is by far one of the more complete REGISTERED JACK references I have seen to date!

***I would encourage EVERYONE to read it!!! This should provide some perspective to dis-spell the misuse and misapplication of the RJ terms!

That is a very good reference, LkEERIE!


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