Polarity tester for 9 core cable

[Spearce]

Hi everyone I am trying to build a simple cable polarity tester can anyone help. I thought I had made one using LEDs and resistors and a 9volt battery but all I have made is a continuity tester. Cheers

 

[jackorocko]

what is a 9 core cable?

 

[davenn]

Hi Spearce
welcome to the forums

are you just trying to prove that all 9 cores are ok and none are open circuit ?

D

 

[Spearce]

9 core cable

Sorry I should of explained better. The 9 core cable has a connector each end one male one female. What I need to do is test that position 1 wire on the male goes to position 1 on female and so on. I have using a DMM but I need now to make a test jig. Thanks Steve

 

[jackorocko]

then wouldn't a continuity tester be ideal?

take another male and female connector and wire them 1 - 1 through 9 - 9. if the cables match up correctly it would light the LED because the circuit was complete. I don't get the polarity issue...

 

[Spearce]

Thanks for reply. The problem I have is I want to make sure wire 1 male con pos 1 goes to pos 1 female con and doesnt go to lets say pos 2. I have had a few leads where this has happened. The way I have built my test box at the moment because I have linked all the male end wires to the battery - so my problem is I can have a wire out of position and it still lights up the LEDs. Sorry if I am making this hard than it sounds I am not that technical.

 

[(*steve*)]

Have a look at this circuit. It is described for 8 wires, but can be expanded for up to 10.

You can use a 555 or similar to generate the pulses required to step through the tests of each wire.

 

[duke37]

That is an elegant solution but could perhaps be improved by having another line of leds showing the transmitted signal. Then a matching pair of leads would show that the correct wire was connected to the right place.