Author Topic: EEVblog #315 - Korad KA3005P Review/FAIL  (Read 144876 times)

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Offline EEVblog

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Re: EEVblog #315 - Korad KA3005P Review/FAIL
« Reply #100 on: July 21, 2012, 03:55:50 PM »
I noticed that the input rating says 220v. I knew an electrician who had a fight with and air conditioner company whose machine was rated 220v and then claimed that it was not covered under warranty because it had been wired to Australian 240 volts.

Australia is not officially 240V any more. It's 230V
http://en.wikipedia.org/wiki/Mains_electricity_by_country

Dave.
 

Offline Ed.Kloonk

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Re: EEVblog #315 - Korad KA3005P Review/FAIL
« Reply #101 on: July 21, 2012, 04:00:21 PM »
I noticed that the input rating says 220v. I knew an electrician who had a fight with and air conditioner company whose machine was rated 220v and then claimed that it was not covered under warranty because it had been wired to Australian 240 volts.

Australia is not officially 240V any more. It's 230V
http://en.wikipedia.org/wiki/Mains_electricity_by_country

Dave.


Bastards. They just stole ten volts from me.

Give it back!

 

Offline SeanB

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Re: EEVblog #315 - Korad KA3005P Review/FAIL
« Reply #102 on: July 21, 2012, 04:16:46 PM »
Ed, a lot of compressors are wound for 200V, as this saves copper in manufacture. Of course it will overheat........ But again most are connected with undersize cabling anyway, so it evens out, warmer wire and cooler windings. Note that they are still marked 220v in this case.
 

Offline IanB

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Re: EEVblog #315 - Korad KA3005P Review/FAIL
« Reply #103 on: July 21, 2012, 04:22:11 PM »
Australia is not officially 240V any more. It's 230V
http://en.wikipedia.org/wiki/Mains_electricity_by_country

Dave.

You should definitely measure the actual voltage at your mains sockets and see what the meter says. My guess is that if the system was originally designed for 240 V then it is still 240 V. It is a huge cost to change installed infrastructure to a different specification. It is much cheaper to change the voltage on paper by adjusting the allowable tolerance.
I'm not an EE--what am I doing here?
 

Offline David_AVD

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Re: EEVblog #315 - Korad KA3005P Review/FAIL
« Reply #104 on: July 21, 2012, 04:38:51 PM »
Yes, when we changed to the 230V standard it was only on paper.  Just the tolerance was changed.  I still measure 240V - 245V at the socket.
 

Offline HackedFridgeMagnet

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Re: EEVblog #315 - Korad KA3005P Review/FAIL
« Reply #105 on: July 21, 2012, 05:02:03 PM »
One point I'd like to make is that Trio Smartcal's ISO:9 whatever accreditation didn't prevent them from selling what seems to be a bit of dodgy junk, one that fails and could possibly damage whatever it is attached to.
I don't know how this PSU could come under the banner of quality assured. Not when the manufacturers details are sanded off half the chips.

I don't suppose Trio Smartcal is going to publish the relevant parts of their QA manual. So we can be sure they followed it when they decided to put this PSU in their range.
If  Trio Smartcal were interested in assuring quality, they should put into their QA manual, "Dont sell equipment that contains chips that have their details sanded off."

ps. I don't think Trio should actually do this, they should just skirt around the QA stuff like we all do.
After all ISO QA accreditation is just a sales tool, one that lets you sell to Government and big companies, and helps keep small companies out.
 

Offline TRIO_Smartcal

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Re: EEVblog #315 - Korad KA3005P Review/FAIL
« Reply #106 on: July 21, 2012, 05:30:45 PM »
Things have certainly been getting interesting.  More questions to answer and here's a bit of an update.

1. What are doing about those we have sold?
 - We are already contacting the customers to advise them of the issue. They can have a full refund, or if the unit has survived Dave's treatment after modification, they can have their unit modified and returned.  Korad has told us they are sending enough parts to modify all the remaining supplies we have in stock and those we have already sold.

2. What if it fails after modification?
- If it fails after whatever modification we need to do, then we will give customers their money back , or exchange for another brand at a preferential price on a case by case basis.  We will then have a totally different discussion with Korad.

3. The transformer Rating?  - It is rated 240V.  We had delivery delays because Korad only had 220V trannies when we first ordered. I suspect they didn't think of changing the sticker on the back.

4. Connections for USB and RS232 on front or rear?   I suspect if someone is hooking this up to a PC they don't want a serial or USB cable coming out the front as well as the supply leads and getting mixed up in the bench spaghetti.  The USB is for PC connection not a memory stick so if it is rack-mounted or on a shelf above the bench, it is probably better on the rear panel. But that's a simple matter of personal preference ultimately.

5. Someone else mentioned the ATTEN APS3003S-3D 
- This is a triple output supply and we sell truck loads of them.  They sell for $249+gst off our website.   Compare that to what you get from the big nationals.  We offer it with a 2yr warranty. We have sold several hundred of them with with just one warranty claim. It is a good supply for the money. And it's a linear. And heavy!    http://triosmartcal.com.au/dc-bench-supplies/2432-atten-aps3003s-3d-dual-power-supply-0-30v-3a.html

6. Uncle Vernon is very correct in pointing out this forum is not a place for racial stereo-typing. We also deal with multiple suppliers from USA, Europe and Asia and we have had no real problems so far.  Dealing directly with manufacturers is OK. They are looking for a long term relationships so you help grow their business and in my experience all those we have dealt with have been fine. It also comes down in the longer term to dealing with companies that you trust and the proof is when something goes wrong, as it has here.  Trust is something that builds with experience and Korad is a new supplier for us, so we need to see how things develop.

So far Korad has been responsive, Dave is copied on emails between us and Korad so he can back me up if he chooses. 

7. Whether Korad knew of the problem when they shipped to us is another issue, and if they found out later there was a batch issue, then leaving the problem for the distributor to find is not the best policy. Also it would depend when they found out be it last week, month, several months ago,  I don't know the answer. But I do need to know.  I have also asked for serial numbers of affected units. 

8.  The sample we tried in our lab was from a different batch to the production units we have in stock. Dave does not have the sample we tested. That is in my garage, works fine, I use it for a quick charge on my boat battery and it comes in very handy.  Dave tested an early production unit, hence my concern and the immediate withdrawal of the product from sale.

9. Why did we take it on in the first place?
Their products looked good on paper offering a good performance at a very reasonable price and down into the education market level and hobbist level. These PSU's  filled a hole in our portfolio for a low-cost programmable supply and as one we tested met it specs we gave it a go.  As I mentioned in an earlier post I have no problem submitting anything we sell for Dave to evaluate. If Dave finds something we don't then that's good for everyone.  How this Korad situation now develops remains to be seen. I will certainly keep this thread posted with developments.  We are just as intrigued as you are!!  Korad's true business ethic and customer care will certainly come out now.  If they do not rectify the situation then they are gone from our range and we take back those we have sold offering the remedies above. It's that simple.

10.  Someone else mentioned that the next supply they buy will be a low cost Agilent. Well I'll declare my bias as Agilent's biggest distributor in Aussieland and say that I totally agree.  We sell Agilent bench supplies at less than Agilent's list price.  That means they start price from us at just $336 +gst. See here :
http://triosmartcal.com.au/1571-agilent-u8001a-dc-power-supply-30v-3a.html

For those in the market for one now, Agilent has an great offer on the E36xx series of bench supplies.   If you buy a qualifying power supply from their E36xxA range for upwards of about $530 +gst they (we) will give you a U1272A multimeter for free. The meter sells for about $440 including gst.

http://triosmartcal.com.au/2251-agilent-u1272a-dmm-digit-water-dust-resist.html

Click on the banner here to see the offer.  www.triosmartcal.com.au 

11. If anyone has further questions about this Korad situation and you can't wait for a post to be answered, then why not just drop me a PM. It goes straight through to my in-box at work. If I have the answer then I'll let you know, and if relevant to the others following this thread then I'll post it, otherwise if I don't know I'll try to find out.

12. Just measured the voltage from the mains here in Castle Hill.  It was 244.1V

13. We don't check for chips with the lettering removed. I think this is were a grasp of reality helps. Why would you check for chip lettering on a $199 supply?  To troubleshoot to component level is just not worth it. Companies remove lettering to protect their IP and  big multi-nationals are doing exactly the same. Sure it pisses off geeks who want to know what the chip is, but is that why you buy something? Because the writing is still on the chips?  Most don't.

14. HackedFridgeMagnet thinks that ISO:9xxx  could have stopped this getting into our range. Absolutely not. Look at Dave's first reaction to the product. Even during the tear-down. It came out OK for a $199 supply. In fact the review was going well until it failed. Now that it has failed when it shouldn't have failed is when QA really kicks in, and remember as someone else said, wrapping your head in tin-foil and singing Hare-Khrishna could be in your QA process but it has to be relevant. What has happened here since the failure is relevant the failure was recorded and appropriate action taken. No tin-foil harmed in the process.  As for this comment QUOTE "ps. I don't think Trio should actually do this, they should just skirt around the QA stuff like we all do." ...........  You must work for one of our competitors  ;-)

15. Finally for David_AVD who did a very relevant post in the ShoutBox  QUOTE:  "Some People want the cheapest price and the best service / warranty. It doesn't usually work that way" END QUOTE.  Well that's the challenge we all face as sales and service companies. We want to do just that to have a competitive edge.  Again as stated earlier it comes down to you getting what you pay for so long as you are not being ripped-off which includes after-sales support & service..  It is all a balancing act that we have to perform with the variables in the value equation.

Cheers & keep it coming.
« Last Edit: July 21, 2012, 05:41:36 PM by TRIO_Smartcal »
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Offline Ed.Kloonk

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Re: EEVblog #315 - Korad KA3005P Review/FAIL
« Reply #107 on: July 21, 2012, 05:47:12 PM »
@TRIO_Smartcal

I commend you for having the balls to do what you are doing and for being bold to hand the gadget to Dave, the hardest, most critical in the biz. Good on you.

Don't let them there knockers knock you!

 :)
 

Offline David_AVD

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Re: EEVblog #315 - Korad KA3005P Review/FAIL
« Reply #108 on: July 21, 2012, 05:50:20 PM »
Nice reply.  TRIO Smartcal seem to be doing exactly what I'd expect any decent company to do.

Local support and warranty is often undervalued.  I buy some (usually very low cost) items direct from overseas and when I do, I accept that I am taking a calculated risk in doing so. (in regard to warranty, represented specs or even receiving the item!)

I must admit my fist reaction was to give the Korad unit a miss after Dave's unit went belly up.  Now I'm quite prepared to consider it if the issues are sorted and TRIO Smartcal offer it for sale.  I'm damn glad I didn't jump in for the slightly cheaper option of buying in from USA and having no support.

As for the sanded chips, I accept that's what some manufacturers do.  It only annoys me slightly as a failure of that part would usually mean I'd just buy another unit anyway.

It has to be remembered that this is a low cost power supply.  Much cheaper than any of the other programmable units I've seen.  The way some people are going on you'd think it was a very expensive high end product!  It's all horses for courses folks.
 

Offline SeanB

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Re: EEVblog #315 - Korad KA3005P Review/FAIL
« Reply #109 on: July 21, 2012, 05:53:38 PM »
Add to this there are a lot of residential areas where there are feed in solar supplies where the mains voltage during the day is 260V or more, as the voltage compensation from the supplier is not meant to work the other way and get power fed from the load side.
 

Offline Ed.Kloonk

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Re: EEVblog #315 - Korad KA3005P Review/FAIL
« Reply #110 on: July 21, 2012, 05:54:20 PM »
Nice reply.  TRIO Smartcal seem to be doing exactly what I'd expect any decent company to do.

Local support and warranty is often undervalued.  I buy some (usually very low cost) items direct from overseas and when I do, I accept that I am taking a calculated risk in doing so. (in regard to warranty, represented specs or even receiving the item!)

I must admit my fist reaction was to give the Korad unit a miss after Dave's unit went belly up.  Now I'm quite prepared to consider it if the issues are sorted and TRIO Smartcal offer it for sale.  I'm damn glad I didn't jump in for the slightly cheaper option of buying in from USA and having no support.

As for the sanded chips, I accept that's what some manufacturers do.  It only annoys me slightly as a failure of that part would usually mean I'd just buy another unit anyway.

It has to be remembered that this is a low cost power supply.  Much cheaper than any of the other programmable units I've seen.  The way some people are going on you'd think it was a very expensive high end product!  It's all horses for courses folks.

This is why I don't understand why Gerry Harvey got nailed when he went after Ebay. He for some reason forget to ram home the point about local service that we all enjoy but sure miss when we bypass it.  :-\
 

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Re: EEVblog #315 - Korad KA3005P Review/FAIL
« Reply #111 on: July 21, 2012, 06:08:43 PM »
This is why I don't understand why Gerry Harvey got nailed when he went after Ebay. He for some reason forget to ram home the point about local service that we all enjoy but sure miss when we bypass it.  :-\

Perhaps because of HN and other discount appliers (generally illegal) attitude towards warranty and customer support. Once that card is swiped they don't want to know you. The expectation being you should seek out the manufacturers service company. The established retailers just don't get it. Which is why they are losing out to online retailers. Often times you can be better looked after by an online vendor.

The vendors that support their products, who provide price and specifications online and those who are prepared to interact with new media are the ones who will benefit and grow.
 

Offline HackedFridgeMagnet

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Re: EEVblog #315 - Korad KA3005P Review/FAIL
« Reply #112 on: July 21, 2012, 06:22:11 PM »
Quote
13. We don't check for chips with the lettering removed. I think this is were a grasp of reality helps. Why would you check for chip lettering on a $199 supply?  To troubleshoot to component level is just not worth it. Companies remove lettering to protect their IP and  big multi-nationals are doing exactly the same. Sure it pisses off geeks who want to know what the chip is, but is that why you buy something? Because the writing is still on the chips?  Most don't.

14. HackedFridgeMagnet thinks that ISO:9xxx  could have stopped this getting into our range. Absolutely not. Look at Dave's first reaction to the product. Even during the tear-down. It came out OK for a $199 supply. In fact the review was going well until it failed. Now that it has failed when it shouldn't have failed is when QA really kicks in, and remember as someone else said, wrapping your head in tin-foil and singing Hare-Khrishna could be in your QA process but it has to be relevant. What has happened here since the failure is relevant the failure was recorded and appropriate action taken. No tin-foil harmed in the process.  As for this comment QUOTE "ps. I don't think Trio should actually do this, they should just skirt around the QA stuff like we all do." ...........  You must work for one of our competitors  ;-)

Ps. I am a reluctant calibration customer, not a competitor.
Just so people are clear, I am not knocking Trio Smartcal or the the way you are handling this situation. I have to say you are going to lengths that I can't remember any distributor ever going. Well done, may it continue.
I am also not knocking you for selling inexpensive stuff rather than just the name brands. Sometimes it's every bit as good.

But I am knocking the QA accreditation system and the way sales people use it to imply that Quality is Assured when it is clearly not, because you don't know who made the chips, when they were made or even what they are. Do you even know if they are Pb free. If so how?

And I would be interested to know what your QA manual does say about how you check equipment before you sell it. Though I guess you will have to 'skirt around' answering this one. I can understand though.


 

Offline amyk

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Re: EEVblog #315 - Korad KA3005P Review/FAIL
« Reply #113 on: July 21, 2012, 09:46:15 PM »
After rewatching the review it looks like more than just the power transistors failed; why would it switch to the 56V tap when the preset voltage was far lower? I'd think that a good control loop would notice the abnormally high output voltage and go to the lowest tap, then maybe even detect that the voltage is still too high and shut off completely at the relays.

56V also looks a bit high for a supply that's rated for only 30V.
 

Offline madires

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Re: EEVblog #315 - Korad KA3005P Review/FAIL
« Reply #114 on: July 21, 2012, 10:48:38 PM »
A friend of mine bought a cousin of the Korad unit - its a Quakko HY3005DP. Along with the infamous full output power for 1 second on power on, it has some other serious problems. I've taken apart the unit, and it does have significantly different construction internally when compared to the Korad.

He cooked his PS in almost the exact same conditions, and it exhibited almost exactly the same failure mode. ETA: (As the Korad did in Dave's video.)

I am sad to say I also have one of these HY3005DP, and it's a total pile of crap. I don't run it at high loads, so it still works, but next time I am getting an entry level Agilent.
-PbFoot

Please read http://blog.mastechpowersupplies.com/ (top entry)

The special feature for pre-setting the current limit is absolutely gorgeous :-)))

Cheers

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Offline T4P

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Re: EEVblog #315 - Korad KA3005P Review/FAIL
« Reply #115 on: July 22, 2012, 04:22:00 AM »
After rewatching the review it looks like more than just the power transistors failed; why would it switch to the 56V tap when the preset voltage was far lower? I'd think that a good control loop would notice the abnormally high output voltage and go to the lowest tap, then maybe even detect that the voltage is still too high and shut off completely at the relays.

56V also looks a bit high for a supply that's rated for only 30V.
Maybe the relays failed and switched in all 3 taps? All did the transistors go short and recieved all 3 taps
It does sound like there's 15-15-0-15-15 to me
Dave, how many taps are there on the PSU?
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Online amspire

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Re: EEVblog #315 - Korad KA3005P Review/FAIL
« Reply #116 on: July 22, 2012, 11:31:14 AM »
But I am knocking the QA accreditation system and the way sales people use it to imply that Quality is Assured when it is clearly not, because you don't know who made the chips, when they were made or even what they are. Do you even know if they are Pb free. If so how?
It is not up to QA to second guess the designers.

It is up to QA to act when an issue of quality arises, which Trio Smartcal have done pretty brilliantly.

It is not just the cheap Chinese products that have batch problems. I own a bunch of  HP 49G calculators thanks to a major batch problem that HP had. They had a batch of leaky capacitors that they used to back up memory as you change the batteries, and the result was the calculators wouldn't turn on. Change the capacitor and they work perfectly. To my knowledge, this problem affected just about every calculator using this batch of capacitors.

Are you suggesting that no-one should sell HP calculators?

Batch component problems happen in manufacturing, and the important thing is the response of the manufacturers and suppliers to this problem. It can happen to any manufacturer using components from any supplier.

It could be that this Korad supply has a design problem, and the correct response from QA is to to see that either the problem is fixed, or to recommend the product be dropped.

Do you have any problem in the way Trio Smartcal have responded?

I have never heard of any QA department of a distributor requiring that a third party manufacturer detail the source and date of manufacturing of every component in a piece of equipment that they make.

Richard.
« Last Edit: July 22, 2012, 11:39:00 AM by amspire »
 

Offline jeremy

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Re: EEVblog #315 - Korad KA3005P Review/FAIL
« Reply #117 on: July 22, 2012, 05:47:03 PM »
Just putting it out there, but I want one. Two actually. Looks like a nice unit for small automation tasks. Hoping to hear from the guys at trio soon.

PS: stuff goes wrong guys. No-one is immune, not even NASA: http://articles.cnn.com/1999-09-30/tech/9909_30_mars.metric.02_1_climate-orbiter-spacecraft-team-metric-system?_s=PM:TECH
If Korad (and by extension, Trio) are going to fix it, then I'm happy. You'd get the exact same treatment if your 9000 series Agilent scope popped.
 

Offline HackedFridgeMagnet

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Re: EEVblog #315 - Korad KA3005P Review/FAIL
« Reply #118 on: July 22, 2012, 10:04:58 PM »
Quote
It is up to QA to act when an issue of quality arises
I was under the impression that Quality Assurance is about preventing these issues arising.
If they do arise then it is about preventing them from arising again.
These are lofty goals, and I subscribe to them, but my experience of ISO:9000etc is that it doesn't necessarily assure anything except a lot of ticked boxes.

 

Uncle Vernon

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Re: EEVblog #315 - Korad KA3005P Review/FAIL
« Reply #119 on: July 22, 2012, 10:12:47 PM »
Quote
It is up to QA to act when an issue of quality arises
I was under the impression that Quality Assurance is about preventing these issues arising.
No it's about tracking and managing process so action can be taken when events arise. The word Quality should never appear in the title.
Sadly however more often than not QA is used as a blunt instrument to restrict or price out emerging competitor. It is also a tool for government authorities, insurance companies and large corporations to duck-shove blame and avoid accountability.

The we have lots of folders full of stuff so it can't possibly our error syndrome. Like throwing buckets of money, a short time- frame and some unrealistic expectations at an industry, while remaining three steps removed from the people who do the work. Then when all the roof batts catch fire and people start getting electrocuted you can blame fly by night contractors and obfuscate yourself from any responsibility. Worked for Kev, Pete & Julia.
« Last Edit: July 22, 2012, 10:18:15 PM by Uncle Vernon »
 

Online amspire

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Re: EEVblog #315 - Korad KA3005P Review/FAIL
« Reply #120 on: July 22, 2012, 10:17:11 PM »
Quote
It is up to QA to act when an issue of quality arises
I was under the impression that Quality Assurance is about preventing these issues arising.
I do not think the QA department is meant to be capable of magic, or predicting the future.
Quote
If they do arise then it is about preventing them from arising again.
Trio Smartcal removed the supply from their catalog until the problem is identified and sorted. Then they will probably decide whether to sell it again or not. It sounds to me like they have done everything possible to prevent the problem happening again
Quote
These are lofty goals, and I subscribe to them, but my experience of ISO:9000etc is that it doesn't necessarily assure anything except a lot of ticked boxes.
ISO9001 is just a standard that makes you define the quality assurance procedures in your company, and ensures you follow your own procedures. You tick boxes if the QA procedures that you defined require you to tick boxes. If you have to tick boxes, you cannot blame ISO9001.

When you are assessed to see if you meet the 9001 standard, they check that your company is following the QA manual that you wrote for the company.

The procedures are as good or as bad as you make them. When a company like Trio Smartcal advertise that they are 9001 qualified, it indicates the company has written QA procedures, and that customers can expect the procedures are followed. This is important for customers like government departments.

Richard.
« Last Edit: July 22, 2012, 10:28:31 PM by amspire »
 

Offline HackedFridgeMagnet

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Re: EEVblog #315 - Korad KA3005P Review/FAIL
« Reply #121 on: July 22, 2012, 10:59:26 PM »
Quote
The procedures are as good or as bad as you make them. When a company like Trio Smartcal advertise that they are 9001 qualified, it indicates the company has written QA procedures, and that customers can expect the procedures are followed. This is important for customers like government departments.

Well now I am confused,
They have written procedures, apparently about QA but possibly not about the quality or the testing of the equipment they sell.
The procedures are about how they react if an issue of quality comes up.
I am supposed to trust them to carry out these procedures because they are accredited. Fair enough, but still they write these procedures themselves so I don't know what they are unless they tell me.
I don't feel much safer.

Sorry for being disingenuous Richard, but I feel you are too.
Quote
I do not think the QA department is meant to be capable of magic, or predicting the future.
Testing equipment before selling it is quite common.
Documenting these test procedures is also quite common.
Using these tests to estimate failure is quite common.
The fact that these tests are apparently not part of Quality Assurance is news to me, but I am not QA expert.
I did not mention magic.


I think you missed this part of one of my posts Richard.
Quote
Just so people are clear, I am not knocking Trio Smartcal or the the way you are handling this situation. I have to say you are going to lengths that I can't remember any distributor ever going. Well done, may it continue.

 

Offline taemun

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Re: EEVblog #315 - Korad KA3005P Review/FAIL
« Reply #122 on: July 22, 2012, 11:50:42 PM »
The test with the constant load of 50W where output was dropping to 0.2 volts was understandable at the electronic load would present an almost dead short when the supply output was switched on. A better test is to use the load switch on the dummy load to turn the constant power load on and off. This way the electronic load sees the set supply voltage and only switches in the appropriate current load for the power setting.

I think this was mostly overlooked, and (to my mind) is the correct interpretation of *that* 'fault'. Constant wattage is pretty much useless for switch on testing.

I groaned when I saw the teardown, the overall internal build was very reminiscent of my Jaycar MP3087. That unit has no fan, and badly needs one when powering a high current load - a 100W LED will make the output transistors untenably hot in a relatively short period. Also, its regulation was so poor that you could visibly see the current (in CC; or voltage in CV) ripple in the LED's light output.

[Edit: in particular, I noticed the chassis had the same dodgy roof rails which didn't meet the front panel at a right angle.]

On the other hand, I can't say enough good things about Agilent 6632B's. A few of them fell into my lap a year ago. They can source or sink 20V/5A (yes, it'll sink full rated power). Sinking is incredibly useful, as is the 20mA (1uA resolution) current sense mode, when dealing with small project power supplies. Testing switch-mode PSU efficiency couldn't be easier.

The 6632B fan is noticeable, and entirely current load based, but these are really designed for rack-mount use, and I doubt that most folks care how much noise their equipment rack makes - it means the units stay cooler and hence last longer.

Considering that you can buy that Korad for $US 75 on AliExpress (plus postage), I wouldn't expect anything good to come from them. Sticking "Lab Grade" on a product doesn't make it so.
« Last Edit: July 22, 2012, 11:56:37 PM by taemun »
 

Offline nixxon

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Re: EEVblog #315 - Korad KA3005P Review/FAIL
« Reply #123 on: July 23, 2012, 01:53:23 AM »
"Considering that you can buy that Korad for $US 75 on AliExpress (plus postage), I wouldn't expect anything good to come from them. Sticking "Lab Grade" on a product doesn't make it so."


I have only seen the D and not the P(rogrammable) version at AliExpress...

nixxon @ iPhone in Ste.Maxime, France at the moment...
 

Online amspire

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Re: EEVblog #315 - Korad KA3005P Review/FAIL
« Reply #124 on: July 23, 2012, 02:26:27 AM »
Testing equipment before selling it is quite common.
Documenting these test procedures is also quite common.
Using these tests to estimate failure is quite common.
The fact that these tests are apparently not part of Quality Assurance is news to me, but I am not QA expert.
They did test the supply before offering it for sale, and their test supply worked. How can you estimate failure when the supply does not fail in tests?  It is a very cheap programmable supply, so they would not expect it to be a top quality design and build.

The unit Dave got was from a different batch, and it was working for most of Dave's review. It was not faulty initially. It failed while Dave was testing.

Quote
I think you missed this part of one of my posts Richard.
Quote
Just so people are clear, I am not knocking Trio Smartcal or the the way you are handling this situation. I have to say you are going to lengths that I can't remember any distributor ever going. Well done, may it continue.
If you are not knocking Trio Smartcal's QA, what on earth have you been whinging about?

Even for the manufacturer, QA and QC (quality control) are two completely different things, and I think you think they are the same. Do you understand that a company with the highest QA standards can choose to sell a cheap low quality product without any conflict of the QA standards?

Lets get back to basics.

One power supply has failed. The supplier has taken appropriate action. A big tick for the supplier. It appears the manufacturer has been communicating with the supplier and seems to be taking appropriate action. So so far, a tick for the manufacturer.

Failures exactly like this can happen with any company and with products of any price.

Let's acknowledge everyone who has done the right thing, let's see what happens, and just move on. There are people in this forum wanting to see if the manufacturer can resolve the problems, as they see the supply as something very useful at the price, even if it is a cheaper construction, and even if the boards are not cleaned as well as they could be.

Richard.
« Last Edit: July 23, 2012, 11:42:39 AM by amspire »
 


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