USB DSO Scope Probe ?

[jfls45]

I just bought the Hantek DSO-2090 which came with two PP-80 probes.

They are x1-x10 passive probes. When I change the attenuation in the software I have the following choices:

Probe Voltage Range Settings
X1 = 10mV to 5V
x10 = 100mV to 50V

The probe manual states:

Max input Voltage
X1: <200V DC+Peak AC
X10:<600V DC+Peak AC

So if I hooked the probes up 500VAC it would display only 50VAC on the scope? Is so, that is a result of the attentuation of the probes?

I just want to make sure I understand how to use these so I don't fry something.

Jeff (brand new member-1st post)

 

[duke37]

500VAC is 707V peak, well above the limit on the X10 probe.
Using the X10 probe with 50V input, the scope will show 5V.

 

[jfls45]

So if I were to probe 120VAC I would not damage the DSO unit or my laptop? At 120VAC would I only see 50V on the computer (or would I damage something)?

Thanks

 

[jackorocko]

So if I were to probe 120VAC I would not damage the DSO unit or my laptop? At 120VAC would I only see 50V on the computer (or would I damage something)?

Thanks

if you want to just look at the waveform, you could probably just use a transformer to bring the voltage down to a safe level. I don't think it would effect the signal much.

 

[(*steve*)]

So if I were to probe 120VAC I would not damage the DSO unit or my laptop? At 120VAC would I only see 50V on the computer (or would I damage something)?

Thanks

Any guide to using any type of oscilloscope generally tells you that connecting the probes to the mains is a thing you should be (at least) very careful about.

The problem is that the ground lead on the probe is directly connected to the ground of the scope, which in turn should be connected to your power ground.

If you try to measure the mains by connecting the ground to one side of the mains and the probe tip to the other then you are effectively using your oscilloscope to ground one side of the mains.

Depending on where you are in the world, at best you'll provide another neutral link to earth, but at worst you can make your scope live and kill yourself when you touch a knob to adjust something. And there's a whole range of things in between.

Just don't do it.

As jackorocko suggests, measure a low voltage signal from a transformer.

 

[jfls45]

Where Ground a USB PC Scope?

Any suggestions where I should ground the USB to PC Oscillscope?

Any guide to using any type of oscilloscope generally tells you that connecting the probes to the mains is a thing you should be (at least) very careful about.

The problem is that the ground lead on the probe is directly connected to the ground of the scope, which in turn should be connected to your power ground.

If you try to measure the mains by connecting the ground to one side of the mains and the probe tip to the other then you are effectively using your oscilloscope to ground one side of the mains.

Depending on where you are in the world, at best you'll provide another neutral link to earth, but at worst you can make your scope live and kill yourself when you touch a knob to adjust something. And there's a whole range of things in between.

Just don't do it.

As jackorocko suggests, measure a low voltage signal from a transformer.

 

[jfls45]

step-down transformer

I took your advice and pulled a transformer out of an old genometer that was junked. The primary = 120Vac and gives multiple secondaries, 2.5, 3.5 4.2. 6.1 and even 250V. Exactly what I needed.

if you want to just look at the waveform, you could probably just use a transformer to bring the voltage down to a safe level. I don't think it would effect the signal much.