spark tester circuit diagram

can anybody please help me with a spark tester circuit diagram with output voltage selection from 0kv to 15kv with display of set voltage and pick up sense of fault detected

Is this for an ignition engine?, what kind of faults are you looking for.

I am looking for extruded electrical cable insulation pinhole faults

the cable under test passes through a bunch of steel beads that is connected to the high voltage output and the cable core is connected to earth.

looking for an old school Clinton type insulation spark tester circuit diagram thanks

john potgieter said:

the cable under test passes through a bunch of steel beads that is connected to the high voltage output and the cable core is connected to earth.

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The place I used to work at had those on the machines that made sparkplug cable. They onl detected a bad spot in the cable, not a measurement in the amount of "bad". They only detect when the high voltage goes to ground, the high voltage was a set amount.

shortbus= said:

The place I used to work at had those on the machines that made sparkplug cable. They onl detected a bad spot in the cable, not a measurement in the amount of "bad". They only detect when the high voltage goes to ground, the high voltage was a set amount.

Click to expand...

Going back MANY years we used to repair equipment for a local company, they were called 'holiday detectors' (and according to google still are), essentially they used a small inverter to generate about 500-600V (going from memory), and this was used to detect pin holes in painted surfaces. The company did research on rusting metal underwater, such as on oil rigs.

Presumably it was asimilar type of unit?.

I said MANY years ago, as I recall the units used Germanium transistors

i recall seeing one that passed enameled wire through water, but that was a long time ago. you could use a hipot tester, and set it to the voltage you want to test. the probe wire could be connected to the test medium, and the take-up motor plugged into the DUT outlet. when the tester reads a conductive spot in the wire, the DUT outlet shuts off so you can inspect the wire.

Nigel Goodwin said:

Going back MANY years we used to repair equipment for a local company, they were called 'holiday detectors' (and according to google still are), essentially they used a small inverter to generate about 500-600V (going from memory), and this was used to detect pin holes in painted surfaces. The company did research on rusting metal underwater, such as on oil rigs.

Presumably it was asimilar type of unit?.

I said MANY years ago, as I recall the units used Germanium transistors

Click to expand...

Was probably similar,but the test was for somewhere around 15K volts(don't know for sure). It was on the out feed of an autoclave that semi cured a layer of silicone rubber on sparkplug wire. They called it a "wet test" because it was coming right out of the autoclave. After the wire was made it had to sit in storage for ~2 weeks before it could be sent to the wire fabrication lines, to finish 'curing'.

That was at GM Delphi Packard Electric. The made, at one time everything for the wires used in cars, from the raw materials. I'm talking electrical tape, copper wire of all gauges, terminals plug wire ,connectors both plastic and rubber, and the nylon pellets to mold the nylon parts.

Probably the best way to detect flashover, and I've seen this in industrial equipment is to use a choke in the ground line to the inverter or power supply, and have a comparator connected across the choke, a flash will create a voltage drop across the choke which is easily detected.
The choke will also to an extent limit the power going into the flashover.
Were you thinking of designing/building something, or do you need something ready done.