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Hantek HT20COP probe safe to use or not?

Pappy19

I brought the PicoScope 2204a recently that has the +/- 20v max voltage input. The HT20COP secondary ignition coil probe has a 10:1 built in attenuator. 
some direct injection engine secondary coils can output up to 40kV even with a 20:1 attenuator added into the line I can potentially still damage this 20v max scope? 
Voltage max protection spec is 100v but I’d rather not use a cop probe if there’s any risk. I have the hantek HT25 ignition lead clamp pickup also that has its own ground clamp. Maybe that be safer to use. Thanks very much if anyone can point me in the right direction if I wanna use this in an automotive application. Maybe il just stick to 20:1 attenuated primary voltage patterns. I assumed a secondary COP probe touching a coil only picks up a waveform pattern until I found out it’s attenuated. I guess it just comes down to myself not knowing much about scopes in general 

  • 0

    Hi,

    I wouldn't do it, unless you can confirm what those probes do (I didnt see anything useful in the one-page manual that I found).

    The 2204A is not an automotive 'scope, I doubt it has any isolation. It would be good to directly talk to Picotech, they specialise in automotive testing so they would recommend what you need.

    If you're intent on using your own combination, then it's probably worth using a cheap almost throwaway laptop, or getting a cheap scope that isn't attached to a PC, rather than risk damaging a more expensive computer.

  • 0

    Look carefully at the probe datasheet. If its truly an ignition coil probe, it should have more like 1000:1, which still is beyond the 20v rating of your Pico Scope. You can use a 1000:1 probe from Tektronox or LeCroy. If your ambitions and handy, you can even make your own 1000:1 probe using a large res like 100 meg to 1000 meg on the input and perhaps around a 1meg or less on the bottom. Side so your scope zin won't affect the reading too much. You'll need a compensation cap around the large input resistor if you want any accuracy beyond a few kilohertz. You can find documentation on how to compute the exact values if you look for it. And dont forget,  the compensation cap must be a high enough voltage or higher than your input hv signal.

  • 0

    The Hantek probe is a non contact probe - and probably magnetic because it's intended for Coil On Plug ignition systems.

    This Youtube shows you how the probes work, and the guy deserves kudos for doing it really cheap !

    https://www.youtube.com/watch?v=Y3KNT4uHnRU

    Waving the Hantek probe near ignition cables probably wont do much harm but may not measure much useful either.

    I wouldn't recommend attempting a 40kV probe at home - mine looks like this:

    there should be a picture of it here but although I easily found the empty box where it's kept the probe wasn't in it Cry

    It's about 30cm long and has  a big plastic guard on it - you need a lot of 500V resistors in series to stand off 40kv - and good luck finding a 40kv capacitor - although you can put one in // with each resistor.

    MK