Which scope with isolated inputs?

[nctnico]

I need to select an oscilloscope for one of my customers. I think it is best if they get one which has isolated inputs so the can measure between any random point without needing to care about common grounds. I've looked at the Fluke Scopemeters 190 series but their memory is very short. Keysight has similar devices but they don't seem to have isolated inputs. So far the best I have found is the BK precision 2515 (2 channels 60MHz) but I'm wondering if there are better choices.

[richpike]

Rohde just introduced a new handheld with isolated inputs:

https://www.rohde-schwarz.com/product/rth-productstartpage_63493-156160.html

-Rich

[commongrounder]

What is the purchase budget?  The least expensive isolated input, handheld scope is the Hantek DSO-1000S series.  They have 1meg memory.

[HighVoltage]

Take a look at the Tektronix THS720P or the newer successors

[nctnico]

As usual the Tektronix offerings are ridiculous. The BK precision I have found is around $2200 and has 1 or 2 Mpts. The THS3000 series only has 10kpts and costs twice as much.

[PedroDaGr8]

As usual the Tektronix offerings are ridiculous. The BK precision I have found is around $2200 and has 1 or 2 Mpts. The THS3000 series only has 10kpts and costs twice as much.

I am almost 100% certain that the BK Precision 2515 is a rebadged Siglent SHS1062, while the BK Precision 2516 is a rebadged Siglent SHS1102. The Siglent version costs about half of the price of the BK Precision rebadge.

[robert_]

If you want something with any kind of performance:
R+S RTH. Around 4k-ish for a decent version.
We already saw a demo of this one, and its by far the best option for anything with isolated channels.
NO comparison to anything from Tek or Fluke. Both of these are 20year old designs (Tek THS720/THS2000 is based on the TDS220/224...)

[nctnico]

I looked at the R&S and this seems like a nice option but for some reason it does not have CAN decoding. I'll skip the BK precission/Siglent due to the usual Siglent firmware problems according to several threads on this forum.

[nidlaX]

You could give the Micsig a try. I had a play around with one a few weeks ago, and the interface really isn't that bad. If anything, they need better manuals, but the UI and keypad designs of every handheld scope ever are basically cloning the Scopemeters anyways.

Also, this guy made a few videos about the Siglent: https://www.eevblog.com/forum/testgear/siglent-shs-1062-review/

[pascal_sweden]

How come that the isolation adds so much to the cost?

Would it become cheaper if scope manufacturers would introduce isolated front-ends in scopes for the masses?

It almost seems like a contradiction that entry scopes for dummies do not have isolated front-ends to cope with beginner's mistakes.

Every scope directed for the educational market should include an isolated front-end in my opinion, and it should be more than affordable if Rigol and Pintek enter a strategic partnership.

Best of both worlds: Chinese digital scope and Taiwanese isolated probe

When will #1 at Rigol take up the phone to make call with #1 at Pintek? =)
Looking forward to the joint press release in China and Taiwan!

[Macman]

How come that the isolation adds so much to the cost?

Would it become cheaper if scope manufacturers would introduce isolated front-ends in scopes for the masses?

It almost seems like a contradiction that entry scopes for dummies do not have isolated front-ends to cope with beginner's mistakes.

Every scope directed for the educational market should include an isolated front-end in my opinion, and it should be more than affordable if Rigol and Pintek enter a strategic partnership.

Best of both worlds: Chinese digital scope and Taiwanese isolated probe

When will #1 at Rigol take up the phone to make call with #1 at Pintek? =)
Looking forward to the joint press release in China and Taiwan!

It does add significant cost to provide isolated inputs with a high bandwidth.

Why would Pintek be of any help. They don't produce any isolated probes. They do make a range of differential probes but that is a different from isolated probes.

[tautech]

As usual the Tektronix offerings are ridiculous. The BK precision I have found is around $2200 and has 1 or 2 Mpts. The THS3000 series only has 10kpts and costs twice as much.

I am almost 100% certain that the BK Precision 2515 is a rebadged Siglent SHS1062, while the BK Precision 2516 is a rebadged Siglent SHS1102. The Siglent version costs about half of the price of the BK Precision rebadge.

I'm quite sure you're correct and this is not the only Siglent rebrand in the BK Precision range.
http://www.bkprecision.com/products/oscilloscopes/2515-60-mhz-1-gsa-s-non-isolated-handheld-digital-storage-oscilloscope.html
http://www.siglentamerica.com/pdxx.aspx?id=93&T=2&tid=2

I looked at the R&S and this seems like a nice option but for some reason it does not have CAN decoding. I'll skip the BK precission/Siglent due to the usual Siglent firmware problems according to several threads on this forum.

I'm not aware of any outstanding FW issues with either of these Siglent SHS series and they share the same FW for the 800 and 1000 models. Off the top of my head these have been around for ~4 years, maybe more.
AFAIK the only difference is the SHS1000 series have the isolated channel inputs.

[hibone]

To me it appears that most of the insulated oscilloscopes out there are hantek or siglent or owon, in different clothes, usually.

Each and every one of the oem version seems to have it's quirks and bugs. Althought the rebranded ones may have a firmware from a completely different manufacturer, and thus some of the bugs may be fixed.


Depending on the needs of the user, a second hand  tektronix THS700 series may be most convenient solution. To get one at a decent price may require a little bit of time, but ebay or government sales may offer good chances.
 
If a more performing one/new/4 channel model is required, up to my knowledge, Chauvin-Arnoux/Metrix has a fairly complete set of products, and may be worth to look at.

IIRC, Fluke is quite limited functionality wise and connectivity wise. The same hold for the Keysight models.

Another approach would be to ask for a demo, so that you have first hand experience of the firmware quality.

[pascal_sweden]

How come that the isolation adds so much to the cost?

Would it become cheaper if scope manufacturers would introduce isolated front-ends in scopes for the masses?

It almost seems like a contradiction that entry scopes for dummies do not have isolated front-ends to cope with beginner's mistakes.

Every scope directed for the educational market should include an isolated front-end in my opinion, and it should be more than affordable if Rigol and Pintek enter a strategic partnership.

Best of both worlds: Chinese digital scope and Taiwanese isolated probe

When will #1 at Rigol take up the phone to make call with #1 at Pintek? =)
Looking forward to the joint press release in China and Taiwan!

It does add significant cost to provide isolated inputs with a high bandwidth.

Why would Pintek be of any help. They don't produce any isolated probes. They do make a range of differential probes but that is a different from isolated probes.

Aren't those the same thing?

Note that Pintek is working on a 100 MHz low-voltage high-sensitivity differential probe that works nicely together with the upgraded Rigol DS1054Z. They could integrate this probe in the actual scope. I am not saying they would have to do it for all 4 channels, but they could do it for 2 channels.

This would add around 300 USD in current pricing levels, but in case it becomes a mass product, the additional price might be reduced to 150 USD as a whole, which I definitely would be willing to pay for the extra level of security.

For reference:

My original email to Pintek:
"Hello,

I read more information about the DP-30HS differential probe.

Really nice feature set.

Only a pity that you don't have the low voltage (65V) high sensitivity (1mVrms) differential probe in 100MHz version. If you would have 4 of those differential probes, you could turn an upgraded Rigol DS1054Z into a fully-fledged 4-channel 100MHz digital isolated scope :)This would be a unique piece of equipment!

Why does high bandwidth (100 MHz) always go hand in hand with high voltages (+1KV)?

Do you see my point about low voltage, high speed differential probe with 100 MHz?
It could turn every hobbyist's 100 MHz scope into an isolated scope, without loosing bandwidth. Hobbyists working on digital design projects, need the bandwidth, and at same time can make mistakes when measuring in their circuits. So I believe it makes sense.

Regards,

Pascal"

The feedback from Pintek:
"Dear Pascal,

Thank you for your e-mail.

I have passed your info to our engineer.
We will develop a new model of different probe.
The spec is:
Bandwidth: 100MHz,
Voltage: 65V
Sensitivity: 1mVrms

By the way, can you please let me know your location? In Europe? Or US?

Thank you"

[tautech]

How come that the isolation adds so much to the cost?

True isolation requires all I/O's to be isolated as well, quite doable but costs money and time, not to mention PCB space.

Would it become cheaper if scope manufacturers would introduce isolated front-ends in scopes for the masses?

It almost seems like a contradiction that entry scopes for dummies do not have isolated front-ends to cope with beginner's mistakes.

ATM cost, and until a manufacturer is brave enough, things will stay the same as they are now.

Every scope directed for the educational market should include an isolated front-end in my opinion......

HELL NO.
How could one teach safe scope use basics? 

Scenario:
Technician graduates, gets employed, connects employers DSO to a DUT as he/she would have at Uni and BANG. 
OK they didn't know any better.   

[tautech]

It does add significant cost to provide isolated inputs with a high bandwidth.

Why would Pintek be of any help. They don't produce any isolated probes. They do make a range of differential probes but that is a different from isolated probes.

Aren't those the same thing? Note that Pintek is working on a 50 MHz low-voltage high-sensitivity differential probe that works nicely together with the Rigol DS1054Z. They could integrate this probe in the actual scope. I am not saying they would have to do it for all 4 channels, but they could do it for 2 channels. This would be around 300 USD in current pricing levels, but in case it becomes a mass product, the price might be reduced to 150 USD as a whole, which I definitely would be willing to pay for the extra level of security.

Please provide source for this claim.   

[hibone]

Strictly speaking no. They are not.

Isolated front-end means galvanically  isolated.
Depending on the implementation, the signal may be digitized and then the digital data is transmitted over an optical link. In other circumstances a transformer is used.


A differential probe, in a way, puts a very high impedance within the ground loop and that's it.

[hibone]

HELL NO.
How could one teach safe scope use basics? 

Scenario:
Technician graduates, gets employed, connects employers DSO to a DUT as he/she would have at Uni and BANG. 
OK they didn't know any better.   

Indeed, nothing keeps you wary of voltage shocks more than pain...

 

[tautech]

I looked at the R&S and this seems like a nice option but for some reason it does not have CAN decoding.....

I'd be interested to know if any isolated channel DSO has decoding. 

[MagicSmoker]

I have a Tek THS-720P which I bought brand new in 1996 and still use every day, and which is on it's 4th (homemade) battery. I also have a fancy-pants AEMC (or is it Metrix or Chauvin-Arnoux?) OX-7104 which I bought 2 years ago and is already on its 2nd battery (homemade) and which I now only take out of its case when I need to monitor more than 2 isolated channels and/or more than 1 Rogowski current probe. At first I thought my dislike of the AEMC scope was simply because it was new and I was being a stick in the mud, but over time I realized that I preferred the Tek scope because it really does have a superior UI, a better system for handling cursors, and it doesn't need special powered probes... The latter issue is particularly annoying if you work with power electronics (which is a prime reason for wanting isolated/floating channels) because a lot of times you want to clip onto a big bus bar or the like and the rinky-dink little grabber at the end of the probe tip just won't cut it. So I would recommend to the OP that he look for a THS-720P on ebay and make a new NiCd battery for it.

That said, the Rohde & Schwarz model someone suggested above looks pretty interesting...

[pascal_sweden]

It does add significant cost to provide isolated inputs with a high bandwidth.

Why would Pintek be of any help. They don't produce any isolated probes. They do make a range of differential probes but that is a different from isolated probes.

Aren't those the same thing? Note that Pintek is working on a 50 MHz low-voltage high-sensitivity differential probe that works nicely together with the Rigol DS1054Z. They could integrate this probe in the actual scope. I am not saying they would have to do it for all 4 channels, but they could do it for 2 channels. This would be around 300 USD in current pricing levels, but in case it becomes a mass product, the price might be reduced to 150 USD as a whole, which I definitely would be willing to pay for the extra level of security.

Please provide source for this claim.   

For reference:

My original email to Pintek:
"Hello,

I read more information about the DP-30HS differential probe.

Really nice feature set.

Only a pity that you don't have the low voltage (65V) high sensitivity (1mVrms) differential probe in 100MHz version. If you would have 4 of those differential probes, you could turn an upgraded Rigol DS1054Z into a fully-fledged 4-channel 100MHz digital isolated scope :)This would be a unique piece of equipment!

Why does high bandwidth (100 MHz) always go hand in hand with high voltages (+1KV)?

Do you see my point about low voltage, high speed differential probe with 100 MHz?
It could turn every hobbyist's 100 MHz scope into an isolated scope, without loosing bandwidth. Hobbyists working on digital design projects, need the bandwidth, and at same time can make mistakes when measuring in their circuits. So I believe it makes sense.

Regards,

Pascal"

The feedback from Pintek:
"Dear Pascal,

Thank you for your e-mail.

I have passed your info to our engineer.
We will develop a new model of different probe.
The spec is:
Bandwidth: 100MHz,
Voltage: 65V
Sensitivity: 1mVrms

By the way, can you please let me know your location? In Europe? Or US?

Thank you"

I have asked them for a follow-up today:
"Hello Pintek,

I wanted to follow-up about my idea which I suggested last year, about making a low-voltage (65V) high-sensitivity (1mVrms) differential probe with 100 MHz bandwidth.

Did your engineer find a feasible and cost-effective solution for this technical design challenge?

Would it become cheaper if scope manufacturers would introduce isolated front-ends in scopes for the masses?

It almost seems like a contradiction that entry scopes for dummies do not have isolated front-ends to cope with beginner's mistakes.

Every scope directed for the educational market should include an isolated front-end in my opinion.

What will be the next step? A strategic partnership with Rigol to build scopes for the educational market that have isolated front-end?

Best of both worlds: Chinese digital scope and Taiwanese isolated probe =)

Only joking, but it would make sense for the educational market, if the price can be kept down.

Regards,

Pascal"

[nidlaX]

I looked at the R&S and this seems like a nice option but for some reason it does not have CAN decoding.....

I'd be interested to know if any isolated channel DSO has decoding. 

The Micsig can, supposedly: http://www.micsig.com/en/product_detail.asp?id=19
"Serial bus decode   UART?LIN?CAN?SPI?I2C"

[nctnico]

I looked at the R&S and this seems like a nice option but for some reason it does not have CAN decoding.....

I'd be interested to know if any isolated channel DSO has decoding. 

The R&S scope offers I2C, SPI and UART decoding as an option.

[pascal_sweden]

Every scope directed for the educational market should include an isolated front-end in my opinion......

HELL NO.
How could one teach safe scope use basics? 

Scenario:
Technician graduates, gets employed, connects employers DSO to a DUT as he/she would have at Uni and BANG. 
OK they didn't know any better.   

Buy the time the technician graduates, all scopes would be isolated anyhow, if this new paradigm shift becomes a reality, giving everbody the freedom to measure between 2 random measure points. Exactly the way it should have been from day one, as all you want to measure is the potential difference between 2 measure points. Nobody should have to care about which measure point is and has to be ground. Why do you have the tip and the clip in the first place otherwise (2 measure points and not 1!)?. In the current constellation they could even consider to drop the clip as it always has to be ground anyhow

[tautech]

Every scope directed for the educational market should include an isolated front-end in my opinion......

HELL NO.
How could one teach safe scope use basics? 

Scenario:
Technician graduates, gets employed, connects employers DSO to a DUT as he/she would have at Uni and BANG. 
OK they didn't know any better.   

Buy the time the technician graduates all scopes would be isolated, giving the freedom to measure between 2 random points. Exactly the way it should have been from day one, as all you want to measure is the potential difference between 2 measure points. Nobody should have to care about which measure point is and has to be ground. Why do you have the clip and the tip in the first place otherwise (2 measure points and not 1!)?. In the current constellation they could even consider to drop the tip as it always has to be ground anyhow

With 50+ years of scope manufacture behind us now, if it was that easy it would have been done for the masses decades ago. Instead we've had various methods to allow freedom of the probe reference (GND  ) connection, some safe, Differential probes, Differential plugins and other not safe although often used by experienced techs.

Trouble is, we have the 50 years of those scopes on the market nearly all with grounded channel input BNC's so significant change to the existing understanding of safe scope use might likely confuse the novice to thinking they can clip a probe reference lead to anywhere.  Isolated channel scopes are specialist items for specialised use and their additional cost of construction puts them in a league that not all can enjoy.
You can't just modify FW to create one, the HW must be suited for purpose.
HH isolation is a lot easier to design, there are less I/O's to consider and seemingly manufacturers think so too.

I looked at the R&S and this seems like a nice option but for some reason it does not have CAN decoding.....

I'd be interested to know if any isolated channel DSO has decoding. 

The R&S scope offers I2C, SPI and UART decoding as an option.

Yes, but not as one option, however wouldn't it be nice if it was a bench DSO?