I must correct myself, only 11400 A out but 42 kW in!peranders said:Can't say but a hint, where do you need 13000 A at low voltage? Input power is a switched PS of 21 kW, volume about 10 liters.

peranders said:How did you build the board, similar mine?
Have many caps did you have in parallel? Type? Working voltage?
One board had 100 X 220µ/400v and the other assembly was about 500 X 2.2µ/400V (plastic) arranged in a ring for minimal inductance.
LV
Like a 1940's vacuum tube computer.peranders said:We have 3000 caps in a cabinet so the probability to have 100% working is zero.

Can't say but a hint, where do you need 13000 A at low voltage? Input power is a switched PS of 21 kW, volume about 10 liters
Are you building a rail-gun ?
Regards
Charles
I wonder if you could simulate this in LTSpice or similar. Put in the estimated lead inductance and inject some signals. See if any surprising currents or voltages appear.
Also wonder if putting a fusable link between a few sections of the board might not be wise? A penny perhaps?
One place that might have some insights is the University of Rochester (NY) Laser Lab. My info isn't current (no pun intended), but they used large banks of capacitors to fire their laser fusion system. I heard stories of cables would jump right off the ground due to the magnetic forces induced. No doubt they had the same concerns about reliability and might know more about unexpected LC effects.
Also wonder if putting a fusable link between a few sections of the board might not be wise? A penny perhaps?
One place that might have some insights is the University of Rochester (NY) Laser Lab. My info isn't current (no pun intended), but they used large banks of capacitors to fire their laser fusion system. I heard stories of cables would jump right off the ground due to the magnetic forces induced. No doubt they had the same concerns about reliability and might know more about unexpected LC effects.
My bet goes for faulty batch of caps. I have seen bc-337 transistors with reverse polarity and glue to fix components to pcb that turns conductive in the next 10 years so nothing really supprises me.
What do you say about this?In our Failure Report I'll explain more the root of problem.
I'm waiting the result of an external laboratory, after that I will send you our Failure Report / Corrective actions ASAP.
Regarding the max number of parallel capacitors, we have seen the following design:
- max 5 capacitors single ended leads in parallel ( about 10Arms),
- max 10 big snap-in in parallel
- max 6-8 screw terminals in parallel
If I were an electronic designer I should consider this as very important information. Why don't they mention it all? This should be written in RED. I know this is

bernhard, if that was a joke haha : )
If you have never heard of a "rail gun" you ought to google it. It is a really really neat piece of technology!
is it for a magnetic office can crusher? (think water cooler only for can crushing)
If you have never heard of a "rail gun" you ought to google it. It is a really really neat piece of technology!
is it for a magnetic office can crusher? (think water cooler only for can crushing)
I wont buy that. But I am REALLY intrested to hear their explanation...peranders said:
What do you say about this?
If I were an electronic designer I should consider this as very important information. Why don't they mention it all? This should be written in RED. I know this isbecause we have made thousands of units with 14 Arcotronics in parallel and 250 A current capability.
I think the basic problem is unevenness of the surface of the electrode connections.
Panasonic = smooth
Rubycon = smooth
Arcotronics, 1000 uF/35 V = smooth
Arcotronics 1500 uF/35 V = a bit rough surface and a break through in a rough corner
I have got the test report now but it can't convince me. Nice X-ray picutures etc but I still don't believe the reasons for the failures.
Panasonic = smooth
Rubycon = smooth
Arcotronics, 1000 uF/35 V = smooth
Arcotronics 1500 uF/35 V = a bit rough surface and a break through in a rough corner
I have got the test report now but it can't convince me. Nice X-ray picutures etc but I still don't believe the reasons for the failures.
peranders said:I
I have got the test report now but it can't convince me. Nice X-ray picutures etc but I still don't believe the reasons for the failures.
Can you enlighten us about their theories or are they under some sort of NDA?
Sure I can enlighten you but I'll do this soon when I have soldered 5000 caps, will happen this aftersnoon.
5000 caps are tested of the brand Panasonic, not a single one has failed. I think this tell us something. 

peranders said:5000 caps are tested of the brand Panasonic, not a single one has failed. I think this tell us something.![]()
They make reliable cars over there (over here?), too.
TD
10000 caps now, still no failureperanders said:5000 caps are tested of the brand Panasonic, not a single one has failed. I think this tell us something.![]()



16000 caps are running now, no failure at all but in the protoype two more Acrotronics have blown 

Guess what? I have got a statement from Rubycon: Never heard of the problem as Acrotronics describes it.
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