Is this even safe? PL 400 Energy Storage???

wattsabundant

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#4
It's not safe because who knows the state of the caps. They're 30 plus years old. If they've been sitting for a while at a minimum they need to be reformed.
 

Gibsonian

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#5
It's not safe because who knows the state of the caps. They're 30 plus years old. If they've been sitting for a while at a minimum they need to be reformed.
Completely safe if done properly. Most hi fi amps of >200 watts/ch have capacitance in that area. I had a couple Denon amps at 200 watts/ch with 40K per side. I have an Accuphase amp I've never used at 150 per ch with 40 K per side. If you start looking at the hyper expensive amplifiers like Boulder, Krell etc, you will see even bigger energy storage per watt. Cooling would have to occur from above or below, the only thing I don't like about that ebay link. In general like the idea and would love to have about 60K per side for my 700 (1000 WOPL rev D future amplifier). At 500/ch, the WOPL is very low on capacitance per watt even with 20K storage per side for hifi applications. Who knows, bass could improve with reserve power like that?
 

laatsch55

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#6
Completely safe if done properly. Most hi fi amps of >200 watts/ch have capacitance in that area. I had a couple Denon amps at 200 watts/ch with 40K per side. I have an Accuphase amp I've never used at 150 per ch with 40 K per side. If you start looking at the hyper expensive amplifiers like Boulder, Krell etc, you will see even bigger energy storage per watt. Cooling would have to occur from above or below, the only thing I don't like about that ebay link. In general like the idea and would love to have about 60K per side for my 700 (1000 WOPL rev D future amplifier). At 500/ch, the WOPL is very low on capacitance per watt even with 20K storage per side for hifi applications. Who knows, bass could improve with reserve power like that?
To a certain degree Scott, especially at the SPL's you and I listen at.
The hand built monster will be 140,000 per side.
 

wattsabundant

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#7
Completely safe if done properly. Most hi fi amps of >200 watts/ch have capacitance in that area. I had a couple Denon amps at 200 watts/ch with 40K per side. I have an Accuphase amp I've never used at 150 per ch with 40 K per side. If you start looking at the hyper expensive amplifiers like Boulder, Krell etc, you will see even bigger energy storage per watt. Cooling would have to occur from above or below, the only thing I don't like about that ebay link. In general like the idea and would love to have about 60K per side for my 700 (1000 WOPL rev D future amplifier). At 500/ch, the WOPL is very low on capacitance per watt even with 20K storage per side for hifi applications. Who knows, bass could improve with reserve power like that?
I think you misunderstood my intent. I don't have an issue with an outboard supply that is safely implemented. My concern is the potential for catastrophic failure of the capacitor bank if it is not properly checked before being energized. The average buyer on EBAY probably doesn't realize that he is subjecting himself to dangerous conditions. I have seen a loose screw on a cap bank cause arcing. The arcing jumped across the busbar and resulted in an explosion that rocked the building. Fortunately nobody was hurt.
 
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jbeckva

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#8
"Now let me tell ya something Sonny. You don't want to be messing with those cap banks been sittin 'round for 20 years. Now if I were to show ya what would happen if I happen to plug one in....like THIS... "

FireMarshallBill3.jpg
 

jbeckva

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#9
But yeah.. seriously...

I remember hearing about a Lockheed rep working on the "Elgar" UPS that they used to have for my old navy test equipment because ship's power was really REALLY bad (mkay?) for it. It was the size of a walk in closet, with caps that stood a foot tall, about 7 inches wide, and a foot deep. He was shorting out the caps with a bang stick, when unfortunately the supply circuit hadn't been tagged out yet.

People seeing him walk off the ship said he was about as white as a ghost, with a 1000 mile stare... Lucky he didn't get killed...
 

Gepetto

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#10
"Now let me tell ya something Sonny. You don't want to be messing with those cap banks been sittin 'round for 20 years. Now if I were to show ya what would happen if I happen to plug one in....like THIS... "

View attachment 11036
The long wires from that external cap bank to the point of load makes that cap bank much less useful than had it been installed closer to where the actual demand occurs. Wire inductance sets in...
 

wattsabundant

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#11
But yeah.. seriously...

I remember hearing about a Lockheed rep working on the "Elgar" UPS that they used to have for my old navy test equipment because ship's power was really REALLY bad (mkay?) for it. It was the size of a walk in closet, with caps that stood a foot tall, about 7 inches wide, and a foot deep. He was shorting out the caps with a bang stick, when unfortunately the supply circuit hadn't been tagged out yet.

People seeing him walk off the ship said he was about as white as a ghost, with a 1000 mile stare... Lucky he didn't get killed...
I am aware of the Elgar inverters and my experience is with similar inverters. The Elgar field engineers used a water fuse, essentially a 10 amp piece of fuse wire wrapped around a fuse block. when immersed in a bucket of water it would operate at much higher continuous currents. When a short circuit occurred the fuse would open in milliseconds.
 

laatsch55

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#12
The long wires from that external cap bank to the point of load makes that cap bank much less useful than had it been installed closer to where the actual demand occurs. Wire inductance sets in...
Then resistance...
 

Gibsonian

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#14
I think you misunderstood my intent. I don't have an issue with an outboard supply that is safely implemented. My concern is the potential for catastrophic failure of the capacitor bank if it is not properly checked before being energized. The average buyer on EBAY probably doesn't realize that he is subjecting himself to dangerous conditions. I have seen a loose screw on a cap bank cause arcing. The arcing jumped across the busbar and resulted in an explosion that rocked the building. Fortunately nobody was hurt.
Don, I did get ya and didn't even intend to reply directly to your quote as if I was disagreeing with you. Safety is number one. I was just explaining that if done properly, it's a good thing.
 

Northwinds

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#15
"Now let me tell ya something Sonny. You don't want to be messing with those cap banks been sittin 'round for 20 years. Now if I were to show ya what would happen if I happen to plug one in....like THIS... "

View attachment 11036
Bwahahahahahhahahahahhaaaaaa! That's exactly what I was thinkin' sans the shiteatin' smile
 
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