Industrial Tech question - Cable to pass DC voltage and serial comm 1

[DrB0b]

Hello all,
Not sure if we have anyone who is well versed in the Industrial Tech side of things. I have a fairly basic question that could be answered.

We have a 6P6C connector, likely a RJ12, that connects to a 6 wire cable that comes from a serial to RJ12 comm box. That box is powered with 24VDC, I think but will double check. That cable is passing the DC voltage and the serial information. Curious if there is a specific gauge wire or type needed for passing voltage and data. I cant seem to find it and the cable we have has zero markings on it. It is flat and black and looks to be just a slightly bigger gauge than a normal phone wire. I know you cannot use normal phone cable but that is about my extent.

Any help?

Learning - A never ending quest for knowledge usually attained by being thrown in a situation and told to fix it NOW.

 

[robertjo24]

There were a few automation devises that I've seen over the years that use the flat "telephone" wire for comms and power connectivity. Often the serial data speed would be 9600 baud or lower, and the power consumption rather low. A typical flat wire would have 28 AWG stranded wire. As such, you will get about 250mA at 24 VDC. You can get a higher gauge flat wire, maybe 26 AWG, but it wont increase power availability much. A standard Ethernet cable would be 24 AWG.

If you are looking to make a new cable, I would use an Ethernet cable and an appropriate 6p connector for the gauge.

 

[DrB0b]

Thank you for your insight. After doing some testing it is a 10V DC passed on the cable as well as the data. Knowing that 28-24 AWG should be fine does line up with what I was thinking. We purchased 100' of 24 AWG 6 pair flat for repair and retermination purposes so I think we are good. I didn't even think to use Ethernet cable as I know PoE is able to be handled with 24 AWG so worst case we can fall back on that cable.

Thanks for helping clarification on all this.

Learning - A never ending quest for knowledge usually attained by being thrown in a situation and told to fix it NOW.

 

[IRstuff]

28 AWG will result in 6.6 ohms of series resistance for 100 ft

https://www.daycounter.com/Calculators/AWG.phtml

 

[DrB0b]

Thank you IRstuff for the additional info.

Learning - A never ending quest for knowledge usually attained by being thrown in a situation and told to fix it NOW.