Cat5 Wiring Question

[beefdiesel]

Had something weird happen the other day when wiring up a Cat5 run and can't figure out why. Typically whenever I make a straight Cat5e patch cable, I won't follow normal wiring conventions and wire by colors left to right: bl, bl/wht, br, br/wht, gr, gr/wht, or, or/wht. I know this doesn't follow 568B wiring, but I always figured pin 1 on one side still matches pin 1 on the other side and so on.

Well the other day, I was moving a touch panel and needed to run a new Cat5 line. I used my typical wiring method, but for whatever reason, the touch panel wouldn't pull an IP address. It would power up just fine, but wouldn't connect to the network without having an IP. I hooked up a line tester and it indicated continuity on all 8 lines, but the middle pairs were blinking to indicate a fault. It wasn't until I wired both sides up in the 568B method that it finally took off and worked.

My question is, why did the 568B method work here and my way of just putting the color in the same pin on both connectors not work? With 568B, isn't pin 1 on the one connector the same as on the other connecter? I'm maybe missing something, but this one has me confused. Thanks for the insight!

[Cyknight]

There's a reason there is a standard ( these days for structured wiring the standard is A, not B but whatever).

The wire pairs are not twisted equally and using anything but the standard can cause interference vs the intended limiting it. There's more too it but lets mot get too texhnical. Which may well be why you had issues. Depending on the tester this can show up as fault or crossword, sometimes even a short.