View source for Probes



https://w140.com/tekwiki/images/1/19/062-1120-00.pdf
(one book in the tek concepts series, see wiki for other books)

==Tips/Techniques==

===1000x / Differential Probes===
https://www.eevblog.com/forum/testgear/use-of-oscilloscope-probe-x100-vs-x1000/msg5431277
* voltage spikes (always give a buffer)
* circuit sensitive to external loading
* high voltage != high voltage & high amperage
* circuit rise time
* differential probes for high voltage are safer than 1000x probes
<pre>
There's a few things to consider with high voltages and probes.

There is the x10 x100 x1000 etc. Which controls what voltage the scope input will see, and source loading.   
If your scope input can handle 200V peak to peak then using a x10 probe means you scope wont see 200V until the probe is at 2000v p-p.  But obviously you have to take into account spikes on the signal you're measuring, as they will be above your signal voltage. So actually putting 2000V p-p on that x10 probe would be stupid, any spikes would overvolt your scopes 200v max input. So maybe you decide to only use it for measuring 1000V p-p so you have 1000V extra for spikes without damaging your scope. 

Or you might choose to use a 100x probe just because your signal is very sensitive to external loading. So you use a 100x probe even through the voltage of your circuit is low enough for even a 1x probe. In this case you may not be dealing with high voltages at all, so you don't want a probe with a huge amount of insulation that is big and cumbersome to use.

The second thing is the probes size/shape. How safe is it to use it on your circuit.
If you're working on tiny 0.5mA high voltage supply then maybe a typical looking small 10x probe would be fine for that at 1000V.   On the other hand, if you are measuring 1000V that can supply 100A then using that same probe would be crazy. You will see 10x or 100x probes that are huge with large red plastic insulation and others that look like normal probes.  It's not just the voltage the probe and scope can handle, it's the dangers from what you are measuring.

Just because a probe says 10x, 100x or 1000x you can't assume it's ok to use that probe to measure high voltage.
It maybe ok for the scope (voltage wise), but may not ok for you (safety wise)  :)





The voltage rise time of the circuit under test is something to watch out for too. I've blown x10 probes that are rated at 400V with a voltage that jumps to 400V in 1uS. Fast rise times can be a probe killer.





Please don't get me wrong, but as long as you need help to understand the probe characteristics I wouldn't recommend connecting the scope to mains or to any inverter...

What you probably need to do it safe is a high voltage differential probe. With that utility, you do much harder to destroy anything just by its connection. And though it costs around €200,- it seems cheaper than a decent scope or the hospital bill.

Trying to be constructive: Do you know "high voltage differential probes"? Do you want more information about them?

The thing with mains voltage and non differential probes just is that grounding the probe easily causes catastrophy. Even with an isolation transformer, sometimes even with a galvanically isolated scope. With the HV differential probe you really do not need to worry about ground, and even better their inputs are symmetrical. It´s the only way to measure common mode signals, and mains and inverters are always good for (unexpected) common mode distortions.
</pre>
Standard (not high) voltage differential probes can of course be made with two probes, connecting their grounds together (i think - double check that one), and putting the scope in math mode (subtraction).




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