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Products => Test Equipment => Topic started by: mimmus78 on April 07, 2014, 08:57:18 am

Title: How ESD meters works and why they costs so much?
Post by: mimmus78 on April 07, 2014, 08:57:18 am

I tried to found some documentation on this small esd field meters but with no luck. Anyone know how it works? Why they costs so much?

Title: Re: How ESD meters works and why they costs so much?
Post by: mcinque on April 07, 2014, 11:26:01 am

AFAIK, they basically inject a low voltage (like 1Vpp) sine or squarewave test frequency (1, 10, 100KHz) in the component and read the mV dropdown voltage conseguent to his resistance to obtain an ESR value.

The more the frequency rises, the less is the reactance, so the standard test frequency is 100Khz.

At high frequencies like 100KHz is more difficoult to read the milliVolts dropdown (many cheap DMM give up just at 10KHz!), I think is this that makes expensive this instruments.

You can build one on your own or use some alternative methods like this https://www.youtube.com/watch?v=115erzCCxgE (https://www.youtube.com/watch?v=115erzCCxgE)

Hope it helps.

Title: Re: How ESD meters works and why they costs so much?
Post by: BravoV on April 07, 2014, 11:29:20 am

ESD != ESR  :palm:

Title: Re: How ESD meters works and why they costs so much?
Post by: mcinque on April 07, 2014, 11:48:59 am

 :palm: |O :-DD R and D are close on the keyboard...  :palm:

I should learn to read better.

To reply to the thread, I guess they cost much because they should read a wide range of voltages with low currents and therefore they should be much sensitive.

Title: Re: How ESD meters works and why they costs so much?
Post by: mimmus78 on April 07, 2014, 12:26:38 pm

Maybe I found something from another Italian:

http://www.instructables.com/id/Adruino-Based-Electrostatic-Field-Mill/?ALLSTEPS (http://www.instructables.com/id/Adruino-Based-Electrostatic-Field-Mill/?ALLSTEPS)