Fuse AIC rating

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hhsting

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I have engineer drawing that says 240V single phase has 22kAIC. It is in main service fuse disconnect. The job is commericial.

I dont recall 22kAIC as fuse standard rating. Normally they have 65kAIC.

Does anyone know if the above is possible or not?
 
22k is a pretty common for breaker AIC rating. I dont recall fuses with that rating but would have to research.
 
It is possible the engineer is showing you there is 22k available at the fuse ?
A lot of engineering drawings show the available current at various locations,

A quick lance as my Bussmann catalog does not show any fuses with a 22k rating,
 
I would bet the drawing is telling you the minimum AIC that should be installed.
Are there breakers downstream that would be series rated?
 
hhsting said:
I have engineer drawing that says 240V single phase has 22kAIC. It is in main service fuse disconnect. The job is commericial.

I dont recall 22kAIC as fuse standard rating. Normally they have 65kAIC.

Does anyone know if the above is possible or not?
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I mostly use class j or class cc. Both are 200kaic.

I don't recall any fuses rated 65kaic, although many series rated products using j or cc fuses end up at 65k.
 
Side note: Back in the 1980's worked in a halve million square foot plant that used fuses with replacement links. Night mechanics always placed 30 amp links in any fuse that blown even after we started to label fuse size on safety switches.They are only listed for 10 KIAC. This plant had at least six buss ducts rated for 3,000 amps ( 480 volts ). Took over 5 years to replace these fuses with 200KIAC quality time delay fuses. After that retired the two plastic cigar tubes we carried with 250 & 600 volt links .
 
garbo said:
Side note: Back in the 1980's worked in a halve million square foot plant that used fuses with replacement links. Night mechanics always placed 30 amp links in any fuse that blown even after we started to label fuse size on safety switches.They are only listed for 10 KIAC. This plant had at least six buss ducts rated for 3,000 amps ( 480 volts ). Took over 5 years to replace these fuses with 200KIAC quality time delay fuses. After that retired the two plastic cigar tubes we carried with 250 & 600 volt links .
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The first plant "journeyman" i worked with used those and doubled the links for motor loads..fortunately i was reassigned to a knowledgeable journeyman after a short while
 
Jraef said:
If that is intended to mean a MINIMUM of 22kAIC, then I don't know of a fuse that would be that low, so pretty much ANY fuse would meet that requirement.
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Not the cheap Class H fuses, like the NON series.
I am surprised these are still so readily available, they must be extremely profitable. I remember cleaning them out of the paper mill electrical room in the mid 70s.
 
jim dungar said:
Not the cheap Class H fuses, like the NON series.
I am surprised these are still so readily available, they must be extremely profitable. I remember cleaning them out of the paper mill electrical room in the mid 70s.
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OK... yeah, I forget those still exist. Also the REN "renewable" fuses with the screw-on caps at the ends of the cartridge that allowed you to replace the fuse links inside... I remember coming across a big box of the links at an old factory that had been converted to a wedding venue a few years ago. Everyone else is drinking champagne and eating cake, I'm wondering around looking at all the cool old gear that was left behind. Opened up an old fuse panel (that had all of the wires cut off), it had hundreds of those links inside.
 
augie47 said:
The first plant "journeyman" i worked with used those and doubled the links for motor loads..fortunately i was reassigned to a knowledgeable journeyman after a short while
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At this big plant when they purchased a $10 million state of the art custom made machine I wanted to install 60 amp fused safety switched for the 5 made in Germany vacuum pump motors that had an unusual 17.5 HP rating @ 480 volts. They had one of the other electricians install 30 amp fused safety switched with cheap 30 amp renewable fuse links. These fuses blow out links every day so they doubled up links. Eventually the fuses would overheat and burn up. One Saturday when the cheap chief electrician was off and job got canceled at the last minute I replaced the 5 undersized safety switched with 60 amp and installed 45 amp time delay 200KIAC quality fuses and they never blow. Of course boss was not happy that I did the work.
 
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