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Masuring AC lines Vs power conditioned lines using analog scope SAFELY!
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Beamin:
I have a furman AC215 and a tek 2465 scope where I want to see if the power conditioner actually smooths out the mains sine wave. It’s sold to make high end hifi sound better(sounds like bullshit since a high end amp should already have a clean power supply but this could make a difference if you had bad 3rd world electricity or a generator). I’m not sure if the furman isolates the output; it has a three prong but but not sure if the neutral are all tied together) it has a huge toroid in it with what looks like a 1:1 transformer. I have generic probes for the scope. So somethings to keep in mind: the ground on the scope is tied to the neutral line. If you are not isolated this becomes a problem or is this a problem only on old radios (saw it on a MRCarlson video, where he explains if you have a non polarized plug you could accidentally create a short with your scopes ground). Do I have to build a circuit to stop the scope from just becoming a short with the full mains current running through the scope? The probes are 10/100X I believe, they are the standard generic 100Mhz  ones you get for $20 off ebay. The scope has a 50 ohms setting, this isn’t just resistance but something for radios: or if I pick that hook up hot and neutral and 15amps will flow through 50 ohms blowing up the scope? Are scopes like multimeters with very high impedance? I would imagine this would be bad for measuring small signals like logic level. Should I build a circuit that AC couples it some how? What would be required to do it safely? How do I keep out other 60Hz buzz from getting onto the signal? I have played with this scope a few times trying to get oscillators to work and many times picked up the 60hz buzz thinking it was the signal...

alsetalokin4017:
Um... ah.... er.....   STOP!


Have you watched Dave's video on how not to blow up your scope? You absolutely MUST watch and FULLY UNDERSTAND this video before you turn on your oscilloscope again. This is a safety issue of the greatest importance. You can not only destroy your oscilloscope but you can KILL YOURSELF if you don't do this stuff properly and safely.

Sorry for shouting but there seems to be some difficulty with this communication channel.

Your post reveals that you do not understand:
Probe attenuation
Input impedance
AC coupling
Grounding
and a lot of other basic stuff that most of us take for granted.

So STOP! and don't even THINK about trying to scope the mains or anything mains-connected like your "power conditioner" until you have watched Dave's video as many times as necessary and have also absorbed all the underlying concepts.

I will not answer each of your questions in the post above directly because they are kind of like asking a cook "why do you put flour in a cake mix". If you don't already know... you don't belong in the kitchen. Yet....

taydin:
You can use one of the following methods:

- Power the device (Furman) from an isolation transformer.

- Use a differential probe instead of the existing 10/100 probes.

She didn't strike me as clueless as the first responder made it look to be. But in any case if you have no idea what the above means, then by all means, watch Dave's video.
alsetalokin4017:

--- Quote ---The probes are 10/100X I believe, they are the standard generic 100Mhz  ones you get for $20 off ebay. The scope has a 50 ohms setting, this isn’t just resistance but something for radios: or if I pick that hook up hot and neutral and 15amps will flow through 50 ohms blowing up the scope?
--- End quote ---

1. I'll bet a cheezburger those probes are actually 1x/10x.
2. Read that "50 ohms" part again and let it sink in.


Watch Dave's video, or not? Go completely through the beginner's oscilloscope thread, or not? Review basic concepts of electricity... or not? It's up to you, I disavow all responsibility, this post will not self destruct in five seconds.
joeqsmith:
I wonder if you would be better off reverse engineering it, then run it on SPICE.   If you wanted to see how it works on a real AC line, you need some way to perturb the input signal.  It may not be such a simple job to do in real life compared with using a simulator.
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