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What are - for you - the 3 biggest disadvantages of your benchtop DMM(s)?
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Doctorandus_P:
I've thought long and hard about buying a benctop DMM, and decided not to.
The deciding factor was that the boxes are too big. They are some 25 cm deep.
If they had the same depth as a digital scope I very likely would have bought one.

I had a look at the Siglent ...3055. and though about sawing the box in half, maybe relocate the transformer.
The box is almost empty, with just the front panel PCB and a PCB at the bottom which is about half the size of the box. But Also decided against that. I'm not going to spend EUR500 on a DMM to cut he box in two.

Maybe, some day I'll design my own custom benchtop DMM.
Fungus:

--- Quote from: Doctorandus_P on September 04, 2020, 03:40:30 am ---I've thought long and hard about buying a benctop DMM, and decided not to.
The deciding factor was that the boxes are too big. They are some 25 cm deep.
If they had the same depth as a digital scope I very likely would have bought one.

I had a look at the Siglent ...3055. and though about sawing the box in half, maybe relocate the transformer.
The box is almost empty, with just the front panel PCB and a PCB at the bottom which is about half the size of the box. But Also decided against that. I'm not going to spend EUR500 on a DMM to cut he box in two.

--- End quote ---

https://www.aliexpress.com/item/4000343031770.html

bdunham7:

--- Quote from: joeqsmith on September 04, 2020, 03:11:14 am ---
"It's that I want hard proof ..."
I doubt you would ever find it.    BBQ starters will very a LOT.   I have characterized the one I use, presented the data for it and have shown how it compares with IEC waveform.   I would expect completely different results if I went to the hardware store and bought a new one.   BBQ starters are going to output several KV, far beyond the 1.5KV you mention.  Their rise times can be well under 1ns and pulse width is going to be <100ns.    I think the one I used can put out close to 5A peak, far from what the standards call for.   

A beginner may suggest if a meter survives +/-1.5KV DC, it would handle every transient up to that.  At one time I made an attempt to provide some insight on how to harden a cheap UNI-T UT-61E and show how a fast edge can be a problem.  Sadly, most of the people who watched the video didn't seem to care about the approach to solving this sort of problem.   The wiki experts just need to know how to mod their cheap meters. 

--- End quote ---

Meters (well made and well specified) typically have a dV/dt limitation of a few million V*Hz, so your BBQ lighter will greatly exceed that, of course. However, I'd consider it poor design if that limitation was anything other than a thermal limitation on whatever absorbs that high frequency energy. 

I'll drag out my old fried 8842A again, here's a picture of the damaged unit with the incinerated parts removed.  Do you see anything in the picture that might help with that fast edge?  Do you think there's room in a hand-held DMM for this type of protection?  Is there something else that can do the same thing in less space?



bdunham7:

--- Quote from: Fungus on September 04, 2020, 03:53:32 am ---https://www.aliexpress.com/item/4000343031770.html

--- End quote ---

Did you look at the comparison photos where they are demonstrating it with the probes into a power strip and then connected to a 9V battery.  Perfect for the target market!
tautech:

--- Quote from: Doctorandus_P on September 04, 2020, 03:40:30 am ---I've thought long and hard about buying a benctop DMM, and decided not to.
The deciding factor was that the boxes are too big. They are some 25 cm deep.
If they had the same depth as a digital scope I very likely would have bought one.

I had a look at the Siglent ...3055. and though about sawing the box in half, maybe relocate the transformer.
The box is almost empty, with just the front panel PCB and a PCB at the bottom which is about half the size of the box. But Also decided against that. I'm not going to spend EUR500 on a DMM to cut he box in two.

Maybe, some day I'll design my own custom benchtop DMM.

--- End quote ---
The SDM3065X is deeper again !
They can't be too compact without compromising safety clearances or the size for TH components used to withstand the voltages they are rated for.
As for being almost empty cases, I can assure you when the 16ch scanner card is installed there isn't much free space left.
Instruments like SDM's are made to be stacked so while you desire something smaller this also compromises stability of anything stacked on top of it.
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