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Looking for portable oscilloscope

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abgx1:
I am about to buy my first oscilloscope.

It will be used for measuring on frequency inverters (mains 400V voltages up to 16kHz), mains voltages in general, and industry sensors. Additionally, I may use it for car electronics.

Measurements will usually be done on-site, in not-so-easily accessible places (like industry water wells in the middle of nowhere).

After some research, I've narrowed it down to 2 options:

1. Rigol DHO804 https://www.conrad.com/en/p/rigol-dho804-digital-70-mhz-1-25-gs-s-25-mp-12-bit-1-pc-s-2986311.html - not very portable, but can be powered from a USB-C power bank.

2. Voltcraft DSO-2072H https://www.conrad.com/en/p/voltcraft-dso-2072h-handheld-oscilloscope-70-mhz-2-channel-250-msa-s-8-kp-8-bit-handheld-1-pc-s-2380256.html - handheld, with its own batteries.

I'm also considering these probes https://www.conrad.com/en/p/testec-tt-hv-250-probe-300-mhz-100-1-2500-v-107255.html for both of them.

Currently, I use a multimeter for these kinds of jobs, but I feel like I could find problems faster if I could see the actual waveforms.

Do you think it's worth trading portability for a 'better' scope (Rigol), or should I be fine with the Voltcraft?"

Aldo22:
I can't tell you what you need, but I can tell you that these devices are available for less.
The Voltcraft DSO-2072H is an Owon HDS272
https://eleshop.de/messtechnik/oszilloskope/alle-oszilloskope/owon-hds272-handheld-oscilloscope.html

And the Rigol is also available at a lower price:
https://www.batronix.com/versand/oszilloskope/Rigol-DHO804.html

alm:
I'm not familiar with the current products on the market, but I'd definitely look for a scope that can take floating measurements at mains voltages correctly. This means if it has multiple inputs, the reference lead of all inputs should be isolated from each other, the unit should use insulated BNC jacks, and you should use probes made for floating measurements like Stäubli ISOPROBE. Both probe and scope should be rated for CAT III 600V or higher. Note that if the reference lead is at 400V, this is not attenuated by the probe, so the scope would see the whole 400V relative to ground (while the operator holding it might be grounded).

abgx1:
Thanks, I know I can buy them cheaper. I'm not going to order them from Conrad; it was just the first English website I found.

Oh, I see the hassle. But that's a problem only if I measure across two phases, right?

Can I avoid all the problems you mentioned if I measure only between a phase and ground?

alm:
With normal probes and non-insulated BNC jacks, the problem is protection against accidentally touching the reference lead (notice how I don't call it ground clip) to phase, and then touching the ring around the probe or the BNC connector, will shock you. In a mains-operated scope this is no problem because the reference lead is tied to ground, so connecting it tho phase will trip a GFCI / breaker or at least produce a spark and probably vaporize the ground lead. With a battery-powered scope you have no such protection. That's why you see the reference lead on the IsoProbe I showed is much more insulated than that of normal probes designed for grounded scopes.

For a single channel, you want an insulated BNC connector on the scope and a scope that has all exposed metal (like USB connectors) and controls sufficiently isolated from the input connector. For a dual channel scope, you ideally also want the two channels to be isolated from each other, not just from the scope, so that if you clip the reference lead of channel 1 to phase, the reference lead of channel 2 won't be live.

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