DSO: How to read max. voltage specs?

[Aldo22]

Hi
This is something I don't understand but would like to understand in order not to damage my oscilloscope.
It's not about probes/attenuators or RF effects but just the basic understanding of how much voltage can be applied directly to the BNC (DC to 1kHz for example).
If you compare the specs of different scopes, you will notice the following variants:

1: Specifications in Vrms / Vpk / Vpp (where I assume e.g. 300Vrms > ~400Vpk -> ~800Vpp)
2. Values in x1 or x10 mode.
3. Additional CAT ratings
4. it is not always clear whether the maximum voltage to avoid damaging the device is meant, or the maximum measurable voltage.

Here are a few examples of specs:

Siglent SDS800X
Max. input voltage: 1 MΩ ≤ 400 Vpk (DC + AC), DC~10 kHz (No CAT rating)

Rigol DHO800
Max. input voltage: CAT I 300 Vrms, 400 Vpk (DC + Vpeak)

Hantek DSO2000
Max. input voltage: 300VRMS (10X)
Overvoltage Category 300V CAT II

Fnirsi DSO-TC2
Max. input voltage: 1:1 probe: 80Vpp (±40V), 10:1 probe: 800Vpp (±400V)


What does it all mean?
I find the Fnirsi most understandable, with the ±40V

So Rigol and Siglent can withstand 300Vrms on the BNC (1x)? But they can't measure it with max 10V/div?
The Hantek specifications seem to me to be based more on the maximum measurable voltage (8x 10V/div).
Although it says 300VRMS (10X), it has CAT II, whereas the Rigol has CAT 1

Does anyone have a clue?
Simple question, as an example of what I'm asking: Will the Hantek break if you apply +60V DC to the BNC?

Thanks for any enlightenment. 

[Fungus]

The number printed on the front is for low frequencies only and is the maximum voltage at the BNC to avoid damaging the device.

(ie. with a 1x probe)

It will get significantly lower at high frequencies, but that's a whole other topic.

[Aldo22]

The number printed on the front is for low frequencies only and is the maximum voltage at the BNC to avoid damaging the device.

(ie. with a 1x probe)

It will get significantly lower at high frequencies, but that's a whole other topic.

Thank you!

On the front, it says "300V CAT II".
The manual says: "300VRMS (10X)".

What does that mean? 10x?
In other words, can I put 230V mains on the BNCs without breaking it?
It can't measure that anyway with max. 10V/div.

[Zero999]

x10 presumably means with a x10 probe, i.e. a probe which divides the input by 10 and applies frequency compensation for the cable.

It's generally considered a bad idea to connect an oscilloscope's output directly to the mains. The chassis shares the same earth as the mains neutral, which can result in high currents, blown fuses/breakers and at worst smoke, fire and electric shock. A differential probe is the correct way to use an oscilloscope at mains voltages.  There are other ways, but one has to ask such questions, they clearly lack experiance and competence to do it safely.

[Aldo22]

x10 presumably means with a x10 probe, i.e. a probe which divides the input by 10 and applies frequency compensation for the cable.

It's generally considered a bad idea to connect an oscilloscope's output directly to the mains. The chassis shares the same earth as the mains neutral, which can result in high currents, blown fuses/breakers and at worst smoke, fire and electric shock. A differential probe is the correct way to use an oscilloscope at mains voltages.  There are other ways, but one has to ask such questions, they clearly lack experiance and competence to do it safely.

Thank you.

You misunderstood me a bit.
I do know what 10x means. I'm just wondering what applies: The manual or the print on the front of the device?

And no, I have no intention of connecting the oscilloscope to mains.
I just want to know what the specs mean, as the thread title says.

[Fungus]

On the front, it says "300V CAT II".
The manual says: "300VRMS (10X)".

What does that mean? 10x?

With a 10x probe.

If it says "300V CAT II" on the front then it should withstand 300V RMS at the BNC.

Me? I wouldn't do it. I'd use at least a 10x probe always if I was looking at mains, maybe even a 100x probe if I was looking at mains all day long (they tend to have better insulation on them).

It can't measure that anyway with max. 10V/div.

It might not be able to measure/display that voltage but it should survive.

[Aldo22]

If it says "300V CAT II" on the front then it should withstand 300V RMS at the BNC.
..
It might not be able to measure/display that voltage but it should survive.

Thank you, that's the answer I was looking for. 

I didn't actually want to do anything with mains. If I have to, then I use a battery-powered scope.
As I said above, I wanted to know if I could apply +60V DC to the BNCs, for example.
If you read the specifications as 10x and not 1x, then the maximum would be +42V DC.

[kripton2035]

never measure mains directly with your scope
use a differential probe.
or you will break the scope...
there are topics about this on the forum, just search for it.

[Aldo22]

never measure mains directly with your scope
use a differential probe.
or you will break the scope...
there are topics about this on the forum, just search for it.

Thanks, but it was never my intention to measure mains with this grounded benchtop scope.
If I want to stare at a 50Hz sine wave, I use the built in AWG. 
I just wanted to know how to interpret the specs.
It can't hurt to know the limits.