Cable size

[zigzaggy]

Hi
I need to make some servo extension cables for my wing servos. I have the necessary connectors but was wondering on wire size.

I do already have some 10/0.1 cable and was wondering if the cable will be adequate for Mini Servos?

hope someone can help

[deh6]

I'm not familiar with the term 10/0.1 cable. However, if it is the typical 10 wire ribbon cable, then it would work (assuming the length of the extension is a few feet or so).

[Rodney]

I'd use 22 or 20 gage wire for the positive and negative leads. You can get by with 24 or 28 gage for the signal wire.

[zigzaggy]

I'm not familiar with the term 10/0.1 cable. However, if it is the typical 10 wire ribbon cable, then it would work (assuming the length of the extension is a few feet or so).

What it means is that there are ten strands of wire at 0.1mm Dia within the sleeve.

I thinking this is probably OK Thanks.

[deh6]

ten strands of wire at 0.1mm Dia within the sleeve 0.1 mm dia strand is close to #38 which has a resistance of 848 ohms per 1000 ft, or 0.848 ohms per foot. Ten strands makes it 0.0848 ohms per foot. This in the #28-#29 range.

Since the + and gnd carry the current, each foot of sero extension makes 2 feet of current carrying wire, or .17 ohms per foot of servo extension length. A Futaba S3003 has pulses of about 0.5 amps, the average current varying with the servo load. So, 0.5 amp through 2 feet of servo extension would drop the voltage around .17 volts. It looks adequate for short lengths. Of course if you have a bigger servo, then the voltage drop may be a bit high.

For long runs and/or a big servo you could double up for the + and gnd wires, which is roughly equivalent to #25. I use #22 for my servo extension, and as Rodney points out you don't need heavy wire for the signal...electrically, it can be "finer than a hair", but mechanically one doesn't want to break.