Wiring patch leads

Tech Tips (the Preferred standard is A standard)

The Pairing is based on connecting up Active Equipment in succession. In other words, if you are plugging into most modern devices you just need a straight through lead.


The PSTN Network Uses the Centre Pairs on an RJ45 or Modular Connection, Pin 4 and 5.

Most Analogue and Digital Systems use the centre Pair to connect Equipment. Only Systems that offer Hybrid Technology use two Pairs for Operation.


The standard speed for most networks is 100 meg which only uses 2 Pairs, 1000 Meg systems are starting to become commonplace in the industry and will soon take over 100 meg as the preferred medium.

10/100 BaseT Connection uses Pins 1,2 and 3,6

1000 BaseT Connection uses all 4 Pairs

TS568A Wiring 


TS568B Wiring

Notes for wiring diagrams above:

  1. For making up patch cables, 568-A wiring is by far, the most common method.
    There is no difference in connectivity between 568B and 568A cables. Either wiring should work fine on any system*. (*see notes below)
    3. For a straight-through cable, wire both ends identical.
    4. For a crossover cable, wire one end 568A and the other end 568B.
    5. Do not confuse pair numbers with pin numbers. A pair number is used for reference only (eg: 10BaseT Ethernet uses pairs 2 & 3). The pin numbers indicate actual physical locations on the plug and jack.
  2. Testing of patch leads should be in conjunction with AS NZS 3087 Part 1 and Part 2.