Detecting hole in cable

Hi,

I am a wire and cable manufacturer. There are times where a hole exists during the extrusion process, resulting low IR. It would be of great help if anyone could suggest an equipment or method to detect the position of the hole in the cable.

I have heard of a method whereby, we pump in a high voltage pulse into the wire/ cable. If it cannot flow through, it will cause a spark and burn {the insulation?} (position detected). Are there any better means of detecting the hole?

Thanks.

Hello there,

Could you please tell us something about the cable you are manufacturing? Conductor size in AWG or Sq. mm, voltage rating, insulation type, thermoset or thermoplastic, the number of layers and so on. We cannot see what you see and what you think is obvious!

When you talk about a "hole" in the insulation, it seems as if you are talking about a low spot in the insulation because you suggest that the insulation resistance is reduced but we suspect there is no "hole" right through to the conductor. Is that correct? Could you please be a little more specific? Could you describe what this "hole" looks like?

As far as the test you are talking about, I wonder if it is a water tank test where the reel wire/ cable is completely immersed in water for a period of time and then tested with possibly high voltage AC.

Thank you for your clarifications.

Kindest Regards,
Peter J. Stewart-Hay
Principal
Stewart-Hay Associates
www.Stewart-Hay.com