EEZ Bench Box 3 - Sequel to EEZ H24005

[ResistorRob]

Accepting new orders for this?

[prasimix]

Accepting new orders for this?

Yes, visit https://www.crowdsupply.com/envox/eez-bb3.

Crowd Supply has already ordered a number of units over those that go for the fulfillment of the campaign, so there will be no need to wait any further for delivery. Unlike the H24005 project, the plan with BB3 is to establish production and availability for many years to come. Over time, we plan to add new modules and improved versions of existing ones.

[prasimix]

I'd love to see 2Q and 4Q modules become available, for instance. Don't break that by spending extra to work around one problem now. Focus on a healthy BB3 ecosystem for the long term!

I have been dreaming of a 2Q/4Q solution since the beginning of the H24005 project. However, it does not seem to happen so soon. It has now been more than a year since I was promised a schematic of a highly completed concept that could be used for the first prototype. That unfortunately didn’t happen and I don’t know if it will happen at all. A lot of knowledge and experience is needed for a good 2Q (or 4Q), far beyond my capabilities. Then it is not surprising that there are no such DIY and open source 2Q/4Q. You can easily find a schematic with the LT1970 with an output booster that probably works correctly for simple tasks. I’m not sure how precise its current setting is, how it behaves with the capacitive load and what its transition is between CV and CC mode.
The matter is further complicated if you want to have the setting and reading of the output values ​​over a wide range, which usually means more ranges and thus autoranging. The latter is in itself complex enough for a unipolar, let alone a bipolar power rail.

I will continue to believe that it is possible to make an open source 2Q/4Q solution and I am ready to invest both time and effort to make it happen, especially since we already have very solid and attractive software support for 1Q and I think it can be easily expanded to achieve SMU functionality. I offered to several people to cover their basic development costs as well offered them revenue share. However, it seems that I still have a "chicken and egg" problem because I'm a nobody and real experts, I believe, would rather get involved if it was a well-established business and a well-known brand when reward is much more tangible. 2Q/4Q seems to belong to purely professional domain and there is a huge gap between that world and what is being discussed on this and similar forums. In the end, this should come as no surprise as anyone with a full-time job in power electronics certainly can’t speak openly because the NDA doesn’t allow it.

Going back to the very beginning of this thread it can be seen that SMU was mentioned and not just any one but Keithley 2400! I do believe it is possible to make something between that and the “proof of concept” LT1970 4Q which would be welcome on many benchtops.

[prasimix]

I got yesterday a short update with video how DCP405 modules come out of the reflow oven. It's available on Twitter: https://twitter.com/envox/status/1272448101815648258

[prasimix]

 This week update:

[AlanS]

This week update:

I gather you're hearing the "Sound of Silence"?

[prasimix]

No music ...  no sound ... only a massive dose of silence occasionally interrupted by false promises, and misinformation.

[prasimix]

Yesterday I got tracking number of the first batch of DCP405 modules! They should arrive by the end of this week. Sending a new, bigger batch has been announced for this Friday. I was told that the finalization takes so long because the assembly of the THT components is slow. 

[Kean]

Well hand placed THT is very labour intensive, and I suspect many companies are still short on labour due to COVID.  You wouldn't try to automate THT placement for a small run like this.

Thanks for the update!  I'm not worried too much about the delays.  I'm actually embarrased to admit that I still haven't assembled my pair of EEZ H24005's.  I must try do that before the BB3 arrives...

[knapik]

Have you done much testing for how much power the SK96-84-SA heatsink can dissipate with the fan on? I think a small electronic load module could be a neat idea, but knowing the thermal limits before brainstorming would be handy.

[prasimix]

With fan running it should dissipate 20 W continuously. I like more 2Q DC source then electronic load. DCP405 is already 1Q+ since has down-programmer. To make it 2Q down-programmer power stage should be enforced, and current setting and monitoring need to become bipolar. But, ok, making an electronic load with bigger heatsink to handle e.g. 30 W or more is still a valid idea.

[mairo]

I'd love to see 2Q and 4Q modules become available, for instance. Don't break that by spending extra to work around one problem now. Focus on a healthy BB3 ecosystem for the long term!

I have been dreaming of a 2Q/4Q solution since the beginning of the H24005 project. However, it does not seem to happen so soon...

Going back to the very beginning of this thread it can be seen that SMU was mentioned and not just any one but Keithley 2400! I do believe it is possible to make something between that and the “proof of concept” LT1970 4Q which would be welcome on many benchtops.

Have you tried to reverse engineer one of the commercially available products? There are also several that are based on LT1970. NI, R&S and Chroma all 3 have PXI type 2/4Q supplies that can be found for cheap (under $500) in eBay if patient enough. Sometimes even a non working unit might be good. Keysight's N6700A/B/C 2/4Q modules can be looked at as well + theirs patents.

[prasimix]

Another Tuesday, another update. Writing each new update causes more and more nausea, but I have to believe that this will come to an end one day. As you already know we have been waiting for DCP405 modules for the last more than two months from the Polish company Assemtec Europe, which I entrusted with assembling the modules (although this was not my first choice).
I decided to start informing you in more detail about what is happening, not to make me feel sorry, but primarily so that other creators, who work hard to make their projects come to life, see what problems they may encounter and what they can expect from companies that supposedly know their business and have things under control.
Assemtec Europe, unfortunately, proves week after week that for reasons unknown to me they have nothing under control and then they either give me promises that they seem to know in advance are unrealistic or they simply treat me with silence and ignorance. Last week was no exception.

Here's a little about the dynamics: Last Monday (June 29th) I contacted them by phone because from June 23rd, I did not receive any information on the status of production. To my surprise, an apology follows that on Friday June, 26th they sent the first batch. However, I also found out immediately that it is a small batch (less than 10% of the total amount!), but I got promise that by Friday (July, 03rd) another 300 pcs will be delivered. That didn’t happen nor did I get any apology or explanation for what happened. I contacted them yesterday and find out the following:

I'm very sorry that we didn't manage to send this batch on Friday. There was one problem - the ZD5 diode was placed in a 180deg rotation, so we had to make corrections in all 300 pcs. [...] I got information from M. that there is an unusual description on the diode, which caused the SMT machine operator to make a mistake and he misread the 0deg polarization in the tape on the feeder.

Sounds acceptable, however the problem is that there are two diodes on the DCP405 (ZD1 and ZD5) and the question arises as to how one is placed correctly and the other is not. When asked how it is possible that only one diode is turned, I get a competent answer:

this is a very strange thing, but yes - ZD1 is correct, but only ZD5 is incorrectly mounted...

Problem with process control? But that's not all: in the first test batch I received several months ago, both diodes were turned on, which was immediately reported to them. This obviously did not help to prevent the mistake from happening again. But once more, that's not all: the modules from the first batch don't have that problem! It turns out that they didn't manage to assemble all SMD parts, but they made another test run which in fact passed fine. Furthermore, the announced 300 pieces are not all, so it turns out that even when they are finally sent, we will have to wait for the rest.
As of yesterday morning for who knows how many times I am trying to get the final delivery date of all DCP405 modules. I asked them to let me know vis-à-vis backers and Crowd Supply, but by the time of writing this had not happened.

Whether this is the real situation or not, we will hardly ever find out. It is certain that, as time goes by, all the joy of this project is gradually going away. The joy that existed because you gave us the confidence to bring BB3 project to life. As time went on I also began to wonder if I had ordered software development or PCB assembly which was supposed to be a routine job, or at least much predictable, or not? 

For the end I am sending at least one picture of the working title: BB3 kits at sunset

... to be continued (obviously) ...

[AlanS]

For the end I am sending at least one picture of the working title: BB3 kits at sunset

... to be continued (obviously) ...

Queue music - Miguel Rios - Song of Joy

At least you will have been responsible for a great instrument with many uses for the community. When this is over we will all be better off, and you will have a platform for your next bright idea - and sympathetic customers who know what you've been through.

[exe]

I feel your pain. I can imagine how exhausting it is to keep pushing them and waiting for nothing. Thanks for sharing the company name, it may help others to avoid troubles in the future.

[Andrew McNamara]

I feel your pain. I can imagine how exhausting it is to keep pushing them and waiting for nothing. Thanks for sharing the company name, it may help others to avoid troubles in the future.

It is baffling - sure, stuff does go wrong during manufacturing, particularly at the moment - but why can't they communicate? Language difficulties, maybe? I'm guessing they're operating on a skeleton staff, with people not experienced in the tasks they're being required to do, but if that is the case, why not admit it? Anything is better than silence.

[exe]

why can't they communicate?

Some people/companies have this mentality -- avoiding liability/responsibility by making false promises so that they don't have to deal with the problem. In some cultures it's more common than in others.

In my first company, when things were going wrong, my manager always ordered us to lie about the scale of the problem and true reasons to avoid liability and to calm customers down and have less phone calls. Of course, customers were even more angry because we often couldn't full-fill our promises. Without knowing the real problem customers couldn't make good decisions.

Another rule we had in the company is that we never return money to customers no matter what. Instead we gave them vouchers/discounts/anything but not money. I believe at some point we got such a bad reputation that it started to hurt our sales, and we had troubles finding candidates that would like to work for us. I was ashamed to have that company in my CV, I thought I wouldn't find another job because of reputation of the employer (I'm glad I was wrong).

If there is no liability in the contract for delays or QA issues, then the only option I see is to have a call with them, explain what these delays means to you, and try to make them to schedule daily calls to have updates so that they don't forget. Not sure how much it can help. I wouldn't threaten them with bad publicity yet (they may not be willing to cooperate with customers who want to leave a bad review). However, since my order is delayed because of them, I feel no trouble filling in a bad review for them. But I'm fine to wait until it all resolves.

[prasimix]

At the very beginning it was clear to me that I had chosen a small company and I did not see a problem in that, on the contrary, starting from myself I thought that communication would go faster, open, honest (should I say human?) without complicated and time-consuming escalation scheme in case of problems. From the very beginning, I begged them not to pretend what they are not because neither they nor I am a multinational corporation that has “everything under control”. However, that did not happen. As time went on, and delivery was delayed, I was increasingly treated with silence and ignorance, exactly the opposite of what should be done in crisis management.

Language difficulties exist, at the very beginning they told me that they are not good in verbal, but only in written communication. Looking back now, that should have been a serious warning to me. However, looking at the bright side again, I thought that we would be able to solve all possible problems quickly by email. But this is not the case: in the 21st century, when almost everyone has an email in their pocket, I have repeatedly waited over a week for a response, which is unacceptable even when everything is going well, not when we have a crisis situation. Well, maybe they don’t see any problem in the fact that something that was first promised for the beginning of April, they fail to deliver as it looks even three months after that (and I didn’t order a few thousand modules!).

[exe]

I wish I could speak Polish. What I'd do is I'd try to make them a TODO list of what needs to be done, with deadlines and daily calls. Sorta crisis management 101. If you want, I can try calling them on your behalf and try to arrange that (in English, unfortunately).

[prasimix]

Thanks for the generous offer. I would like to do this myself for now, somehow. Yesterday I asked again to give me the final date for all the remaining modules. An answer like: the rest will be completed in two weeks in a given situation and with the track record of not fulfilling the promised more to me it is not convincing enough. For that reason, I kindly asked them to send everything they have in the next batch that should happen this week: fully completed modules and those that lack THT components. In two, actually three weeks (one extra due to shipping) I have enough time to solder the rest myself and test everything immediately.

I am waiting for an answer and their decision, so I will see how to further escalate it.

[danielbriggs]

I’m just curious, (it doesn’t change anything or my support for this excellent project) but of the modules... how many in total are they expected to deliver? And how many have you had? 300?

Only so it can then be known a rough percentage how far we’re through.

You have all other components / assemblies / kits etc?
It’s just this last module we’re waiting on? Who assembled all the other boards?

[prasimix]

Argh, the numbers definitely don’t work for them: the ordered number of DCP405 modules is "massive" 570. So far, 74 (20+54) have been shipped, and 300 were supposed to be shipped last Friday, but that didn’t happen because they have ZD5 rotated.

All other modules are supplied and packaged. At March, 12th it was said that all modules will be delivered by April, 10th. Today is July, 07th and apparently and if I am lucky I will get everything in three weeks.

[prasimix]

It was hard to imagine that I would need to write a post with this number of weeks. Here we have exceeded half a year and the campaign fulfillment has not been made yet, and here this saga obviously does not end because today I learned the following from Assemtec Europe:

Regarding DCP405 production, we wanted to finish production as soon as possible - just as I talked to you and which we received the "green light" - SMT production for DCP405 was transferred to a subcontractor (a fairly large company, existing for many years on the market and with many good reviews). We were to receive the entire order in a short time, unfortunately they had a machine failure which slowed their production. We agreed with them that this week they would finally deliver the remaining goods so that we could perform THT assembly and send ready devices to you (that's why I wrote that the final delivery will take about 2 weeks - I took into account the time needed for ZD5 corrections and THT assembly). Qualitatively, as you probably saw, solder joints are of high quality. This failure is production line downtime that has no effect on the quality of the devices made.

Sounds good? Yes, like in a fairy tale. Regarding the ZD5 component, the 300 pieces that were supposed to be shipped no later than July, 3rd are still not ready for delivery. I asked them how do they solve the problem of the rotated component? I did not get an answer. The problem with the rotated ZD5 also existed on the test batch, I corrected it myself and it took me about 10 seconds per component, I used two solders. I also asked them if they had ever heard of a “hot tweezers” (see picture below). I didn't get any answer.
Last Thursday they sent me 78 pieces that arrived this morning. Here we come to the "quality of the devices made". By quick visual inspection (using a pair of my eyes , I found that on 42 modules (~ 53%) 5 capacitors are missing! I found another module that lacks a + 5V LDO (nasty thing!) And two on which the MOSFET for the Rsense relay was badly soldered (not so much a nasty thing). 4 modules require deeper analysis because they do not work properly from the first. Total score: 49 problematic modules or ~ 63% failure rate. I am speechless.

A new batch of some 60 modules was sent yesterday. I'm waiting to see if the pick 'n place machine forgot to put capacitors on such a large number of modules.

Looking back we have the following: June, 15th I got from them a short video of the modules coming out of the oven. A month later, 134 modules were delivered to me, if we add about 60 that arrive, let it be 200. That is barely a third of the total amount. I really believe we won’t have to wait the next two months to get the remaining two thirds.

[Andrew McNamara]

Sigh, I feel your pain. These people could not find their arse with both hands.

A "fairly large company" that apparently only has a single dodgy 1980's era P&P machine?

Does the left most board have a scorched silk screen in the lower left?

[prasimix]

Does the left most board have a scorched silk screen in the lower left?

I’ve seen this on several modules. It seems to be a special secret procedure on how to solder a triac . It’s one of the new surprises in this batch because in the previous one it wasn’t the case.
These guys seem to really have trouble soldering THT components.