New R&S 2-Quadrant Power Supply NGM200 - 20Aug2019

[JxR]

I'm still awaiting delivery of my own NGM202, which I've been told it is currently in the "build queue".  Hope to see it soon.  In the meantime, I found a nice review online that someone has posted of this unit:
https://goughlui.com/2019/08/20/launch-day-review-rohde-schwarz-ngm202-power-supply-overview/

I do plan on posting my thoughts on the device as well, once I've spent some time with it. 

I'm specifically interested in investigating:

- Battery simulation performance with the built-in vs custom generated battery profiles.
- Battery charging simulation using the same profiles (only unit I'm aware of that simulates this).
- Real-time (or close to real time) acquisition and graphing of measurement data using the fast-capture mode (500 kSPS).

If anyone is interested in something specific to the unit, let me know and I'll see if I can look into it once I have the unit on hand. 

Big thank you to Rich, and to R&S for the opportunity to test the NGM!

[maginnovision]

Maybe they can upgrade you as a sign of goodwill, hahaha.

Well we joked a bit about it, but that is exactly what is happening  :

Good morning JxR,
I hope this finds you well. A return RMA XXXXXXXXX has been created for you. I have placed an order for a new NGM202 (free of charge) which will ship to you soon. Please return NGL202 SN: XXXXX in your possession once you receive the new unit. Here is the address to ship to....

That's great! I actually mentioned it as BMW has always been fairly generous with Goodwill gestures and your chances were good with Rich here. For a company like R&S it's a much better move than just telling you to keep waiting, at least now you're waiting for something more.

I hope it shows up soon and works well. 

[Rich@RohdeScopesUSA]

Big thank you to Rich, and to R&S for the opportunity to test the NGM!

It was the right thing to do and I was happy to help.  Thanks for your patience 

-Rich

[JxR]

I did receive the NGM202.  I've barely had time to play with it, but I like what I see so far.  I do want to spend some time with it before I say much about it. I already have a couple UI suggestions I plan to run by R&S.

One of my projects I'm working on for the next 1.5 months uses a Li-Ion battery with wireless charging.  I think this will be a good test of the NGM since there are a few more variables involved than the standard battery powered circuit with USB charging (Semtech ICs with Wurth Elektronik coils).  The transmitter and receiver coils/circuit I'm using are capable of 20W, and the NGM had no problem quickly confirming the efficiency at ~81% (not too bad for this type of circuit).  I'm really liking that the NGM allows you to test charging the battery model which is a unique feature.

The cells I plan on using just came in today, so planning on getting a discharge profile built once I have them charged up.  Then see how it compares to the built in profiles.

Thanks again to Rich for the opportunity to test NGM.

[mairo]

Hi JxR, can the NGM create a battery profile by discharging it, similar to what you can do with a SMU (e.g. from Keithley) ?

[JxR]

Hi JxR, can the NGM create a battery profile by discharging it, similar to what you can do with a SMU (e.g. from Keithley) ?

It currently doesn't have that feature.

Although I think it might be possible to add such a feature if they wanted to.  There are relays on the output, so they could technically drain a battery off and on.  Use the force/sense terminals to measure the battery under load.  Then open the relays and take the open circuit voltage reading with the DVM terimals (which work regardless of the output relays being open).  With both measurements, and sink current, should be able to calculate the ESR of the battery at various states.

I think it would put some wear on the relays though.

It is probably already possible to script something like this yourself I would expect. I haven't looked at all the relevant SCPI commands but I'm guessing there is something in there to get the DVM measurement.  Standard volt/current measurements when the output is on is definitely there.

[simone.pignatti]

It looks like this product has been designed to work together with CMU and CMW in production or service lab, where they must buy it no matter the price. The right price range for such product is around Euro 1000.Net - That's my opinion 

[JxR]

The right price range for such product is around Euro 1000.Net - That's my opinion 

Yeah, but then you would still need to purchase the "R&S-NGM-K001: Boots when you press the power button" license for an additional 3700 euro.  They must have decided to just include that license in the base model.  Which honestly is convenient, since it would be hard to put in that license key manually when the unit wouldn't turn on without it.

[simone.pignatti]

The right price range for such product is around Euro 1000.Net - That's my opinion 

Yeah, but then you would still need to purchase the "R&S-NGM-K001: Boots when you press the power button" license for an additional 3700 euro.  They must have decided to just include that license in the base model.  Which honestly is convenient, since it would be hard to put in that license key manually when the unit wouldn't turn on without it.

yes, doesn't matter what options ... 1K is the price, no more

[nctnico]

The right price range for such product is around Euro 1000.Net - That's my opinion 

Yeah, but then you would still need to purchase the "R&S-NGM-K001: Boots when you press the power button" license for an additional 3700 euro.  They must have decided to just include that license in the base model.  Which honestly is convenient, since it would be hard to put in that license key manually when the unit wouldn't turn on without it.

yes, doesn't matter what options ... 1K is the price, no more

It would be great at the price point but the reality is that you can't design & produce a PSU with an extremely accurate measurement unit included for that price. Even from a Chinese brand such a device would easely cost 2k to 3k. It is way beyond a simple bench PSU and well into SMU territory.

[JxR]

It also can take measurements at 500kSPS @6.5 digits of resolution, and can keep up that rate until your usb flash drive runs out of space.  The closest competitor, the Keithly 2281-S is $3k, only 1ch and has a max ~30kSPS @ 3.5digits and can only record 2500 samples. 

Only the Keithley 2461 SMU has a faster sampling rate at 1MSPS, and it can sample and record at that rate for ~2secs (it cost ~$10k). 

The NGM can easily sample for minutes at its fastest rate.  I already did a 30sec sample and it was about 700MB on a 16GB flash card.  So multiple minutes of data for about a $10 flash drive.

[Yashu]

Hi JxR, can the NGM create a battery profile by discharging it, similar to what you can do with a SMU (e.g. from Keithley) ?

It currently doesn't have that feature.

Although I think it might be possible to add such a feature if they wanted to.  There are relays on the output, so they could technically drain a battery off and on.  Use the force/sense terminals to measure the battery under load.  Then open the relays and take the open circuit voltage reading with the DVM terimals (which work regardless of the output relays being open).  With both measurements, and sink current, should be able to calculate the ESR of the battery at various states.

I think it would put some wear on the relays though.

It is probably already possible to script something like this yourself I would expect. I haven't looked at all the relevant SCPI commands but I'm guessing there is something in there to get the DVM measurement.  Standard volt/current measurements when the output is on is definitely there.

The non-reactive model within the NGM200 can only go so far.

The simple Voc and ESR model at the beginning of this video is still pretty good:
https://www.mathworks.com/videos/automating-the-parameter-estimation-of-a-battery-model-95187.html?s_tid=srchtitle

Thanks to the EV craze, Mathworks has great recent models.. even stochastic and neural network topologies.

http://www.yashu.com

[ws2812b]

Rich@RohdeScopesUSA, I was just searching for a for four-quadrant power supply and it looks you also have a variant of the NGM200 which features this? Or is this NGu401 something completely different and just looks the same? Do you know if there is any review anywhere? The only sensible thread in the forum I could find is this one. 

The reason I'm wondering: I saw that you have this promotion in the US (https://www.tequipment.net/Rohde-&-Schwarz/NGU401COM/Source-Measure-Unit/SMU/?v=0) and was wondering if it also available in Austria? If yes and if it is what I think, it would actually fit right into my budget and save me quite some hassle with the bureaucracy 

[Rich@RohdeScopesUSA]

Rich@RohdeScopesUSA, I was just searching for a for four-quadrant power supply and it looks you also have a variant of the NGM200 which features this? Or is this NGu401 something completely different and just looks the same? Do you know if there is any review anywhere? The only sensible thread in the forum I could find is this one. 

The reason I'm wondering: I saw that you have this promotion in the US (https://www.tequipment.net/Rohde-&-Schwarz/NGU401COM/Source-Measure-Unit/SMU/?v=0) and was wondering if it also available in Austria? If yes and if it is what I think, it would actually fit right into my budget and save me quite some hassle with the bureaucracy 

Hi ws2812b - we did introduce a 4-quadrant SMU last week, the NGU401.  While it is in the same chassis as the NGL/NGM, it is a ground up design.  In terms of reviews, I believe some are in progress - hope to see them posted in the not too distant future. 

With respect to Austria, I'm mainly focused on North America, but I do know the promotion is available worldwide (although it is likely at a different price for local currency - I believe it is 4,995 Euros in Europe).  Again, please don't hold me to this - but this is my understanding.  I'd suggest checking with one of our partners in Austria (Datatec, Distrelec or Farnell).

Hope this helps.

-Rich

[ws2812b]

Hi ws2812b - we did introduce a 4-quadrant SMU last week, the NGU401. 

That explains why I didn't see it last month, when I started my search for a four-quadrant power supply a month ago

While it is in the same chassis as the NGL/NGM, it is a ground up design.

I digged through the datasheet and it seems to fit well for me, especially I like the high current range to 8A. But what I also saw: there seems to be some functionality not included in the 401 with respect to the 201??? E.g. this independent DVM. Is there more I should be warned? The high speed logging is in both as far as I understood?

In terms of reviews, I believe some are in progress - hope to see them posted in the not too distant future. 

Cool! Looking forward to this.

With respect to Austria, I'm mainly focused on North America, but I do know the promotion is available worldwide (although it is likely at a different price for local currency - I believe it is 4,995 Euros in Europe).  Again, please don't hold me to this - but this is my understanding.  I'd suggest checking with one of our partners in Austria (Datatec, Distrelec or Farnell).

gotcha, found it! (https://www.datatec.de/detail/index/sArticle/99380) Thanks.

[Rich@RohdeScopesUSA]

Is there more I should be warned? The high speed logging is in both as far as I understood?

The logging is in both.  We have some videos that compare the differences:

NGU201 vs NGU401:


NGM200 vs NGU201:


For people not familiar with SMUs and what they're used for:


-Rich