plus there’s no way to shut off the power to this circuit without pulling these fuses while hot.
yeeesh!
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Thanks for the clarification 
These things interest me, but I’ve never worked in high voltage, and a good thing, I’m quite clumsy and distracted. I’ve even given up working on any valve amplifiers etc. even if asked by friends. Just too spiky for this old heart!
250 volt AC is my limit now
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3 Swiss boxes would fix it for a little over $1,000.
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I’m not exactly brave in these circumstance. I was about 6’ away when I took that picture. Too close for me but I have to figure stuff out and no one knew the fuse size.
First vault I was in (utility and live 12kv) was back in the pager days. I just got the pager and it was on my belt. Lots of exposed, live, buss over my head. I’m trying to act comfortable in front of the experienced utility guys. I received my first page just at that moment. Thought a bolt of lightning struck me in the pants. I buckled to my knees before I figured it out. Everyone had a good laugh!
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I have yet to purchase a audiophile power anything cords, fuses, regeneration device with a UL label from even bigger audiophile labels.
Do they exist in such a niche market?
Love me some Bugge, but this one is just not for me, aurally cool as it is (and it is very cool)…
I was not a big fan of “New Age” music when it was new.
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Lane Tech? Yes. ACB would be the proper choice with Solid State or microprocessor protective relaying. The upgrade, as you say would be pricey.
That’s what hot-sticks are for. Of course assuming the motor contactor is working properly downstream. If it is for a fire protection pump or jockey pump, it is rarely operated, and is not typically continuous duty. An unprotected drop from the main feed got my attention, sheesh is right.
Pagers, damn things! I’ve had more of those incidents than I care for as well. Worst was in a bucket about 18 feet up and moving in toward a 345kV, de-energized line, to inspect a switch and insulator. Entering a 765kV switchyard for the first time was an experience I’ll never forget. hairs standing on end as I passed under a 765kV line. That and providing oversight for a contractor installing jumpers across a three phase switch hot, without hot sticks. Basically a bird on a wire.
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Oak Park River Forest. Good luck getting a hot stick in that cabinet to pull those fuses, not exactly code compliant clearances!
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Yup, a real mess. Wearing an Arc Flash Suit will limit mobility. Yeah, so a hot stick at those clearances isn’t going to fly. Makes one wonder who was the installer, and when. My guess is early 1960’s.
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He was known as “Flash”, but his friends called him"Sparky"
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This is what a more complex circuit breaker system looks like. I’m reviewing a coordination study for a pipe fitters local 597 project and an upcoming meeting (can’t get the switchboard delivered even though it was ordered way over a year ago). This is a 2000A, 480/277V system. Nothing crazy complicated. If you look carefully, you can see overlaps where a 20A circuit failure can trip the lager upstream 50A breaker. Bit of a poor design by my team but nothing critical.
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phwoooaaarrr that’s the kinda detail i like!
i’m intrigued by the number of voltage standards mentioned on this forum, a new one in this post too. as far as i know uk is 240 on single phase/415 volt 3 phase, and other than that it’s much higher - 11,000 v, 32,000, and upwards.
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Memories of my initial EE days on the job, breaker coordination. Fun stuff, and definitely need an eye for detail. There’s a bit of an art to it as well, charts and graphs any take one so far with protection scheme coordination.
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I have a question regarding this whole debate… I have a decent understanding of most of this topic, but there is something that eludes me. I have my power amp plugged directly into a PS audio Soloist, and my line and phono stage plugged into a PS audio PPP conditioner, which is also plugged into a Soloist. So, could I safely bypass the fuses in the amps (with slugs) since the conditioners are protecting them with fuses of their own? I am thinking that if any surges come through the line, they will be protected by the conditioner, and additional fuses in the amps are just overkill. Is this incorrect?
No sorry. Surge and overcurrent protection are very different. The fuse is for overcurrent protection and sized to avoid permanent damage to that particular piece of equipment.
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Well that answers that. I am not taking the chance of bypassing any one of my fuses then. Thank you for the fast reply!
Since I want my system to live up to its full potential, I guess I
will be in the market for a SDFB soon…
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Umm… I thought I can find an escape from see these curves on this forum. Just kiddinng of course. last year, I was buried with reviewing those with tons of solar interconnect project. Finally thought I was seeing the last of it, now this 
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