HOW to Use USB-DSO on 230v AC Mains to workout on AC Dimmer

Submitted by lara on Tue, 10/06/2020 - 20:15


My USB DSO model 6022BE and probe used 10X.

To comply the subject work, I have googled and understood that, need isolation trasformer(1:1, ie, 230v/230v) to protect the PC/DSO/DUT. And it also correct if use 230/12v for 2 nos in cascading connection, ie, Mains-230-12 --12-230v.

So, my questions are:

1) Why cant use the dso on the mains without isolation trf ?

2) is 10x probe sufficient, here dso will take 23v with 10x probe. or should i use 100x?


1. It is a problem to measure the mains voltage using DSO due to the grund loop problem. In such case an isolation transformer may work. But best way is to use two differential proble without connecting the ground. If you are not planning to check mains voltage, it is ok.

2. 10x probe sufficient for what? what is the maximum voltage you will measure?

  Joined February 12, 2018      696
Monday at 02:11 PM

Absolutely do not use the 10x probe which came with the 6022BE oscilloscope, I own one once, and tried to measure 240V(absolutely in 10X mode) mains with this scope, but instead I got a dead scope, this scope is very sensitive to serges, so do not try to measure mains with this scope. i was lucky that did not gave me a dead motherboard, but it did gave me a dead USB though.

  Joined December 02, 2019      117
Monday at 10:02 PM