What precautions should I take while using an Oscilloscope?

[Tanmay Jambavlikar]

I have recently bought a Hantek DSO5102p for educational purposes. Although I know some basic operation of an Oscilloscope, I would like to know what all errors I can make and should be avoided as a beginner using it.

[Jwillis]

Its been posted many times before but that Dave guy has a really good video on that.
Check out his other videos on oscilloscopes and much much more.

[danadak]

Some ref material -


https://www.tek.com/document/technical-brief/floating-oscilloscope-measurements-and-operator-protection


http://in.tek.com/dl/3AW_19134_2_MR_Letter.pdf


Regards, Dana.

[rstofer]

Google 'using an oscilloscope'
There is a Sparkfun video among others.

[alsetalokin4017]

Don't probe the %^$&#& mains !
 

[jasonbrent]

Alright, having watched that video a couple of times... and read the tektronix paper... I've got a dumb question.

I'm using a rigol ds1074z... I've got a device I'm probing that has 3 ground planes.

1) The first is on the AC side. It is grounded to the chassis. When probing the AC components (not the transformers, just bits on the AC side of the board), grounding my probe to chassis is correct, right?

2) For each of the 2 DC areas of the board, the grounding points are less obvious, but I can find one with my DMM and continuity checks. For these components, I should have the scope probe grounded to the associated ground plane of the area of the board I'm probing, right?

... or have I completely misunderstood this video and paper?

-j

[rstofer]

Without seeing a schematic, it is impossible to recommend anything!

Even on the low voltage side, we have no idea how the power supply works and whether it is earth referenced without a schematic.

[jasonbrent]

Without seeing a schematic, it is impossible to recommend anything!

Even on the low voltage side, we have no idea how the power supply works and whether it is earth referenced without a schematic.

Well, if you are game, the schematics are in the first post here: https://www.eevblog.com/forum/metrology/valhalla-2701c-schematics-100832/

... mine is a variant of this that doesn't have the HV side (40V max, in theory instead of 1200V). The schematics identify a 0v and 0v(a) for the isolated and normal ground referenced parts, as best I can tell.. this is honestly my first time digging into schematics.

Before probing anything with the scope, I've (with power off, unplugged..) tried to trace the ground down and verify with continuity checks before powering up...