CAT-5 and CAT-6 control cable notes

This revision is from 2021/02/04 14:51. You can Restore it.

The CAT-5 is very a cheap cable which you can buy all over the world. We use the outdoor FTP version for many years at OL7M contest QTH without any problems. Up to 100m+ it works with Stack Matches, 4SQ-8DIR, and also rotators. At the beginning of year 2021 I receive messages from fellow HAM with some problems. There remains very low voltages at the end of 100m CAT-5 cable and the relays do not switch. I was looked in to the problem and found it. The issue is that CCA wire is used. This is Copper Clad/Coated Aluminum wire. This is an ALUMINUM wire with a very thin coating of copper. Please, keep in mind that aluminum is only about 60% as conductive as copper. Read more:

CCA Cable Should Be Avoided

When network infrastructure budgets are tight, it can be tempting to cut corners where you can. One way we’re seeing attempted cost savings is through the purchase of copper clad aluminum (CCA) cabling systems. Offered as a cost-effective replacement for solid copper cable, CCA cable is anything but an effective solution.

While CCA products might look like (and be advertised to function like) standard Category 5e or Category 6 cabling, there are major differences that could pose network problems, concerns about business continuity, and safety hazards.

CCA Defined

This type of cable has an inner aluminum conductor coated with copper, and is much lighter than solid copper cables. Because CCA cable is manufactured at a much lower cost, it offers higher profits to manufacturers that sell the product. CCA cabling does have its place when used in certain electrical applications to avoid problems with aluminum wire connections, but it’s not a viable substitute for twisted-pair communications cabling.

Source and More at:

BELDEN: CCA Cable: 5 Reasons To Stay Away

DC Resistance problem

  • CCA wires has got almost the double DC resistance than Copper wire
  • Voltage drop is too high and remote box does not work

Please DO NOT USE

  • 25 AWG wires
  • 24 AWG CCA wires for length more than 15m

RECOMMENDED

  • Wires with diameter 24 AWG / 0,5 mm and more
  • Shielded cable - use shield wire as another GND wire - more "fat" = less resistance
  • For length more than 80m is better to use more fat wires 22 AWG, 20 AWG / 0,8 mm and more.
  • For outdoor instalation please use: Jacket: Polyethylene (PE) for Indoor

DO NOT BUY

  • Do not buy CCA wires - COPPER CLAD ALUMINUM(CCA)

There are examples of wrong one:

RIGHT ONE

  • Double check material of wires, must be 24 AWG or lower (23, 22 etc) / 0,5mm and thicker
  • Recommended: Polyethylene (PE) jacket, Shielded
  • Right cables are: Solarix SXKD-5E-FTP-PE, trueCABLE Cat5e Outdoor Shielded (FTP) with SOLID BARE COPPER CONDUCTORS etc
  • Must be: