Wire Harness Tester

Projects General Guidance
1

Hi everyone!

I am quite new to the Arduino world and I'm currently building a project in which I would like to create a prototype of a Wire Harness Tester, using relays. The prototype will perform a test for up to 3 cables. 6 pins (3 for each side of the harness).
The test consist on driving a voltage through pin1, and then waits for a response in pin 2, 3…until pin6.
Then, turn off the signal on pin1, and then do the same thing with pin 2, checking for a response in all the other pins. This will help to detect how the wires are connected.
My first thought was to do it by myself, cause I read about crosspoint switch technique, using a matrix to drive the voltage to every pin I want.

I’m a bit confused and now I don’t know if I followed the correct way to accomplish this.
Is this method adequate?
Any help or suggestions would be welcome!

The voltage used in this prototype will be 5v.

2

Do not cross-post. Other thread removed.

3

Relays ? What ? Why ? They are so slow ! Why not digital signals ?

4

As I said, this is just a prototype. The main purpose of this project is to drive HV in order to test industrial harnesses.

I know it's a fussy project. But this is what I must do.
Hope you guys can help me out with this.

5

Piece of cake.

6

chava-mac:
As I said, this is just a prototype. The main purpose of this project is to drive HV in order to test industrial harnesses.

I know it's a fussy project. But this is what I must do.
Hope you guys can help me out with this.

what is HV ?
if it is high voltage then the first round of testing should be for continuity, the 5v would fine.
then the next round might be high frequency to test the wires
then a voltage that would be 50% - 200% greater than the desired application calls for. at least 80% of the rating of the wires. THHN is rated for 600 volts , so if the desired application were for a 24 volt unit, but the installation has 120volts, I would test the harness for 180-230 volts. worst case is if someone were to wire it wrong and connect to the mains. I would rather short out a wire in testing than have to remove a harness in the field because of some field problems (clumsy mechanics ? )
in most industrial testing one will test a device for 'worst case' and then some.
with only 6 wires, I would use the relays as you mentioned, knowing that the relay will introduce circuit effects of it's own.
but I would have either 6 relays on each end with a light at one and power at the other, or have 6 lights on the far end.