# Molex plug burnout damage this be electrically verified with expensive gear



## kiriakost (Jul 20, 2020)

I am industrial electrician working in the past 10 years with the sector of electrical test and measurement, that is the world of quality multimeter , oscilloscopes , component testers. 
This topic it might be of interest of anyone planning to get education as electrician or electronics engineer. 

At May 2019 in order to test the sensitivity of quality multimeter against dedicated resistance meter,  I did use a round Molex pair of pins (New - Unused) so I to collect statistics.
One year later I got as Gift one damaged PSU 750W due some sort of short-circuit this caused at the CPU 4Pin Plug. 
DC to DC 12V rail (inverter) circuit was unable to activate any protection because it seems that arching this is not included as cause of damage when a PSU this is tested in the production line.

Either way I have some quality resistance measurements to demonstrate at my Blog.  
Beware this is a boring topic for youth and gamers.    






						Resistivity benchmark ONLY for talented Precision benchtop multimeter
					

Resistivity benchmark ONLY for talented Precision benchtop multimeter



					www.ittsb.eu


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## kiriakost (Aug 5, 2020)

My original diagnosis was 100% correct (of why this PSU  got damaged),  the second diagnosis ( of what parts got damaged this was also correct),  after new spare parts arrival and a few hours of surgery the PSU came back in the world of the living. 

Quick tour at my lab.


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## delshay (Aug 5, 2020)

@OP

List the parts you changed with photos. This will make the thread more interesting.


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## Toothless (Aug 5, 2020)

I see a whole lotta expensive and pretty machines


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## delshay (Aug 5, 2020)

Toothless said:


> I see a whole lotta expensive and pretty machines



i also have very expensive equipment

Aoyue BGA 9000A Full Infrared rework station, Aoyue oven for reballing BGA chips. Fluke 225C portable scopemeter & RAMCHECK LX with every single adaptor barring DDR4 adaptors. i don't even want to know how much it cost me to import to the UK.


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## kiriakost (Aug 5, 2020)

delshay said:


> @OP
> 
> List the parts you changed with photos. This will make the thread more interesting.


I am in a mission to teach Pros of the importance of them using quality measuring tools and I stop there (motivation) .
You can verify PSU voltage specifications of 2% if your DMM this is ten times better.

I do not pass detailed repair tips, this is my gift only for my son, the upcoming  third generation in electronics repairs.  



Toothless said:


> I see a whole lotta expensive and pretty machines


The human intelligence which using them this is the most expensive asset.


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## delshay (Aug 7, 2020)

@OP

When I do modding I pass that info to users where possible. User's love to see hardware modding with photos. As long as it work's it does not matter how it looks. You should share your knowledge & experience so that we can have new generation of young users taking up electronics.


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## kiriakost (Aug 7, 2020)

delshay said:


> @OP
> 
> When I do modding I pass that info to users where possible. User's love to see hardware modding with photos. As long as it work's it does not matter how it looks. You should share your knowledge & experience so that we can have new generation of young users taking up electronics.



Actually there is a complete topic about this PSU repair,  but I am afraid that many with out electronics repair background they will be unable to understand the information's. 
Thanks. 





						July 2020 PSU CORSAIR CX750 Repair - CP9020015 - CWT PUQ-G - Quality Monster
					

July 2020 PSU CORSAIR CX750 Repair - CP9020015 - CWT PUQ-G - Quality Monster



					www.ittsb.eu


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## GreiverBlade (Aug 7, 2020)

well, Corsair CX series are not the most reliable (read : they are bad bad) PSU from Corsair, the only PSU i had failing on me was a CX550, and just like the CX750 it was a Great Wall OEM (some are CWT for the CX550, DSAIII iirc ... thus it's a bit of a russian roulette ) although yours is a CWT ... which is a bit weird hummm .... CWT tend to be more reliable than Great Wall 

wait ... is it a CX750M? because the CX750 is definitely not from CWT, the CX750M is indeed a CWT DSAIII

interesting thread


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## kiriakost (Aug 8, 2020)

GreiverBlade said:


> well, Corsair CX series are not the most reliable (read : they are bad bad) PSU from Corsair, the only PSU i had failing on me was a CX550



Just to clarify, occasionally I am servicing a large medical lab this having several PC. 
Indeed I had also* two incidents* with two *CX500* that I got as NEW  *Model CMPSU-500CX V2 *(them be replacing much older PSU ).
Suddenly and after 3 months for the first and 12 months for the second, both computers demonstrated instability and blue screens. 
I am now thinking or speculating,  that something was degraded in them regarding capacitance,  and at an old motherboard with single core CPU this made a big difference.
But interesting enough the same supposed unstable PSU when was installed at more modern MB with lots capacitors on it,  the PSU works flawlessly. 

2) I am no Corsair fan boy  in any way.   I did my research about the specific CX750, prior investing any money for repair parts,  so me to discover and get convinced if this PSU is indeed based on a healthy electronic design. 
The witch hunting shown that indeed this is the latest revision named as CX750 ( the problem free one) which Corsair trusted enough to use also at CX750M. 

3) The time that I spent finding the truth about CX750 this were two weeks, but I did skip a new research of how many revisions could be out there of  CX750M. 
Its true that  Channel Well Technology this seems to be the father of CX750M CP-9020061 ,  I did locate PSU evaluation report from an tester in Cyprus , and I did like the test results. 
ftp://members.cybenetics.report/PDF_Reports/d/cybenetics_Bkm.pdf


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## R-T-B (Aug 8, 2020)

kiriakost said:


> I did locate PSU evaluation report from an tester in Cyprus , and I did like the test results.



That's the same tester who does our PSU reviews, @crmaris

It's clear you know what you are doing here, my appologies for my earlier comments.  I think I just misunderstood some of your comments due to language barrier (don't feel bad, I only speak english and horrible, broken spanish, so you are doing fine).


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## kiriakost (Aug 8, 2020)

R-T-B said:


> That's the same tester who does our PSU reviews, @crmaris


He has no electrical or in electronics  certification , but I do trust the automated report, because they are automated measurements combined in a report.
But here there is also another catch ... if the testing machine this is not send yearly for calibration ( then any later produced testing results they worth nothing at all).


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## R-T-B (Aug 8, 2020)

kiriakost said:


> He has no electrical or in electronics  certification , but I do trust the automated report, because they are automated measurements combined in a report.
> But here there is also another catch ... if the testing machine this is not send yearly for calibration ( then any later produced testing results they worth nothing at all).



You may be right, I am not sure.  I trust his reviews as far as internet reviews go, but you know the standard there can be pretty low.  At least he has a good attempt at it.


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## kiriakost (Aug 8, 2020)

R-T-B said:


> You may be right, I am not sure.  I trust his reviews as far as internet reviews go, but you know the standard there can be pretty low.  At least he has a good attempt at it.


I have no doubt that they are positive intentions.
But mister faganas he cannot conquer the world of electronics as I did, with out any certification at hand.


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## Caring1 (Aug 9, 2020)

kiriakost said:


> But mister faganas he cannot conquer the world of electronics as I did, with out any certification at hand.


It's a piece of paper, it means you were persistent and stuck it out through a course you paid for, it doesn't mean you know more.


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## kiriakost (Aug 9, 2020)

Caring1 said:


> It's a piece of paper, it means you were persistent and stuck it out through a course you paid for, it doesn't mean you know more.



The people which has such of a thinking, usually are the ones thinking that they can steal of what they do not deserve.
The kings in the sector of any science, they are the engineers,  I am qualifying talking with the king, and learn more from him if he make the judgement that I worth it.
No one else can talk with the king, no one else has a door at the real knowledge.
Is google your friend?  How is that when the Kings do not share anything with it.

And about my self, I am sharing in public only 5% of my total knowledge. 
I will never double cross the kings whom trusted me in person and shared with me their knowledge.


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## delshay (Aug 9, 2020)

Caring1 said:


> It's a piece of paper, it means you were persistent and stuck it out through a course you paid for, it doesn't mean you know more.



Agree with you. Some of the very best engineer's out there are self taught. I'm mostly self taught from the age of 12.


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## Frick (Aug 9, 2020)

kiriakost said:


> I do not pass detailed repair tips, this is my gift only for my son, the upcoming  third generation in electronics repairs.






kiriakost said:


> I have no doubt that they are positive intentions.
> But mister faganas he cannot conquer the world of electronics as I did, with out any certification at hand.





kiriakost said:


> The people which has such of a thinking, usually are the ones thinking that they can steal of what they do not deserve.
> The kings in the sector of any science, they are the engineers,  I am qualifying talking with the king, and learn more from him if he make the judgement that I worth it.
> No one else can talk with the king, no one else has a door at the real knowledge.
> Is google your friend?  How is that when the Kings do not share anything with it.
> ...



So you're a feudal technician. Embrace the revolution, son. All kings fall.



Caring1 said:


> It's a piece of paper, it means you were persistent and stuck it out through a course you paid for, it doesn't mean you know more.



Yes and no. A certification is there to try to guarantee a lowest common denominator it the field, and to set up a kind of chain of responsibility. Many professional certs are more or less very hard to just aquire like that, you need a level of knowledge to get them and you get tested regurarly if you want to keep them. Obviously there are plenty of people with certs that should not have them, but it's a very necessary system.



delshay said:


> Agree with you. Some of the very best engineer's out there are self taught. I'm mostly self taught from the age of 12.



But they (and you) still have to get certificates if they want to work on things that require them.


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## kiriakost (Aug 9, 2020)

delshay said:


> Agree with you. Some of the very best engineer's out there are self taught. I'm mostly self taught from the age of 12.



self taught this is a tricky description,  self taught regarding getting new experiences this is more than welcomed at all ages.
But high education this is no free gift,   I think that  @*Frick *he  did get at the point, with out going to school and even elevate your certification there is no well paid job for you. 
Or the worst that usually happens , this is getting hired and then getting paid always as you were a helper.



Frick said:


> So you're a feudal technician. Embrace the revolution, son. All kings fall.



Electrical and electronics both are full of laws and following your King in battle.
If you stay alive and survive all battles, one day you may become a freelancer King too.
While there is no democracy in that, still there is in it of what Americans describe as opportunity


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## R-T-B (Aug 9, 2020)

I mean no offense, but if you are describing this as a freelance king battle, csmarris already has you beat.  He owns a PSU certification company competing with 80PLUS.


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## kiriakost (Aug 9, 2020)

R-T-B said:


> I mean no offense, but if you are describing this as a freelance king battle, csmarris already has you beat.  He owns a PSU certification company competing with 80PLUS.


Electricity and electronics they are sectors with millions of applications, one man alone he is sort to get all of them in hand.
Any one with a specific tester in his hands he may receive  certification company competing verification too.
This is simple as sending an application at EU headquarters and this gets approved.
Now you may have a legal testing lab, if you do hire real engineers.
There is no obligation the owner to be an engineer.


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## R-T-B (Aug 9, 2020)

kiriakost said:


> There is no obligation the owner to be an engineer.



Yes, but he's both the owner and sole tester, pretty sure.


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## kiriakost (Aug 9, 2020)

R-T-B said:


> Yes, but he's both the owner and sole tester, pretty sure.


At the fairy tale, the three little pigs, I am the one which made it home with solid bricks,  and this has benefits. 
Just read only the intro ... 





						U1272A Multimeter
					

ITTSB Blog  Agilent U1272A multimeter review




					www.ittsb.eu
				



and of this too.
https://www.ittsb.eu/Ultra-High-Precision-resistors-Box.html 
Retail value of combined product samples = 6500 $ US 
And as last the Fluke corporation and their vise president. 
https://www.ittsb.eu/forum/index.php?topic=518.0

I think that this topic when a little bit OT but even so  this is now complete regarding introductions.
Thank you.


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## R-T-B (Aug 11, 2020)

kiriakost said:


> At the fairy tale, the three little pigs, I am the one which made it home with solid bricks,  and this has benefits.
> Just read only the intro ...
> 
> 
> ...



I mean he has expensive gear totaling well over that in his lab as well?

You seem to be very interested in trying to impress.  This isn't a contest.  That is my only advice here, as I obviously can provide none other (not certified in this field in any form).

I do wish your thread luck regardless.


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## kiriakost (Oct 14, 2020)

While latest made electrical test and measurement tools , they are sophisticated and truly impressive, the final touch of human intelligence  is the one which will combine them in a way this boosting productivity and minimizing time spent for diagnosis.

This is the final version of my own PSU quick testing harness.
As soon the PSU this is on due it mains switch, the active indication of 5Vsb this is the first sign that there is some life to it.


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## delshay (Oct 14, 2020)

kiriakost said:


> While latest made electrical test and measurement tools , they are sophisticated and truly impressive, the final touch of human intelligence  is the one which will combine them in a way this boosting productivity and minimizing time spent for diagnosis.
> 
> This is the final version of my own PSU quick testing harness.
> As soon the PSU this is on due it mains switch, the active indication of 5Vsb this is the first sign that there is some life to it.
> ...



I have a few of those LEDs including the really tiny version. I use these on old motherboards where voltage can't be detected in software.  Yeah, LIVE monitoring of voltages... Love It   ...Saves time poking everywhere with a meter.


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