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SAISAY
9th July 2014, 03:35 PM
This is a serious question:?
I an not an electronics person just a person with a bit of common sense.
Say you use a cord like a US232 8 pin Data moulded cord that have very thin wires, I do not know the gauge specifications for the wire.
Anyway, my question is:
If you pair the wires and solder them to 4 wires of a higher gauge, does that mean the RS232 wires can carry twice the power?
Such as a stepper motor for a CNC machine 3.1V, 2.5A/phase

I have a CNC machine the keeps on blowing the control box.
My argument is that these wires are meant to carry low voltage data not power a motor.
Am I right in my presumption?
TIA

BobL
9th July 2014, 03:45 PM
Most RS232 cables are designed to carry 10s of milliamps at a few volts so even if you wired 2 of them in parallel they still won't carry 2.5A

dabbler
9th July 2014, 05:44 PM
Sadly data plugs are fitted to power cables.

I have seen brand new equipment fitted with RS232, PS/2, 5 pin DIN and Micro-DIN connectons for power over the years. Their respective power supplies were hardwired at one end with wiring capable of carrying 32, 12 and 5 volts at several amps, and regular plugs at the device end.

The manufacturers obviously thought it was acceptable practice to use data plugs and sockets to carry power.

Mostly things like external drive caddies, but one was a dot matrix printer. Incredibly dangerous as far as I was concerned.

Bob Willson
10th July 2014, 11:23 AM
Anyway, my question is:
If you pair the wires and solder them to 4 wires of a higher gauge, does that mean the RS232 wires can carry twice the power?
Such as a stepper motor for a CNC machine 3.1V, 2.5A/phase
I have a CNC machine the keeps on blowing the control box.
My argument is that these wires are meant to carry low voltage data not power a motor.
Am I right in my presumption?
TIA

Hi saisay
Your assumption is correct. Data cables (even if they are paired or quadrupled) are not suitable for carrying current that will drive a motor. If you have been using them, then I would surprised that you have not melted the cables together.
The size of the cable that is coming out of the motor is the best guide to what the size required is. You can go heavier, but not lighter.
Also, when you say the motors are 3.1v, do not be confused, these motors are commonly run at much higher voltages. Usually at least 24v. In my case I am running the steppers at 70v using the Gecko 203V controllers.
I seem to remember that you won a Gecko 540 at the last Cairns meeting. This means that you should be able to use a PSU up to 50v.