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Products => Test Equipment => Topic started by: MrElectric on January 04, 2020, 05:09:53 pm

Title: Measuring high voltage
Post by: MrElectric on January 04, 2020, 05:09:53 pm

I use my trusty, 30 year old multimeter for most things I need to measure. However, as I would need something that can measure up to 1200 V or so. What are the options? It would only need to be able to measure voltage.

I'm troubleshooting my oscilloscope, which is why I'm interested in measuring high voltages.

One idea I had just now is to make a voltage divider. Just connect the multimeter to the divider box, and multiply the measurement by 10. That would be an easy solution. I would just have to buy high quality insulated cables (5000V or so).

Is this how everyone else measure high voltages?

Title: Re: Measuring high voltage
Post by: David Hess on January 04, 2020, 06:02:50 pm

That is essentially what a high voltage probe for a multimeter has.  Inside there is a resistive divider made from at least one high voltage resistor designed to operate into the input resistance of the multimeter.

Title: Re: Measuring high voltage
Post by: _Wim_ on January 04, 2020, 07:52:51 pm

Some DIY high voltage probes:

https://www.pocketmagic.net/homemadediy-high-voltage-probe/ (https://www.pocketmagic.net/homemadediy-high-voltage-probe/)
http://archive.siliconchip.com.au/cms/A_111937/article.html (http://archive.siliconchip.com.au/cms/A_111937/article.html)

This should give you an idea how to make one yourself that is safe to use.

Title: Re: Measuring high voltage
Post by: MrElectric on January 04, 2020, 09:27:14 pm

Thanks for the replies!

I also found this thread:
https://www.eevblog.com/forum/testgear/howto-measure-high-voltages-with-a-multimeter/ (https://www.eevblog.com/forum/testgear/howto-measure-high-voltages-with-a-multimeter/)