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Safe touching of live circuitry inside amps

10 years ago, we had a 1,200 ft addition built onto our house.

I installed a new 200 amp panel and meter box on the addition which became the main breaker panel and ran a huge romex wire (100 amp rated) from it to the old main box in the garage which then became a sub-panel after the electric company moved the drop from it to the new box.

I ran all of the wiring to all of the outlets and lights, including a sub-panel with breakers in the shop.
Took photos of all of the wiring before the drywall went up. That becomes handy when hanging things on a wall, so fasteners don't hit any wiring.

I drew up a map which shows which outlets and lights are on each breaker and it lives on the front panel of the box.
Did the same for the original part of the house, including the gauge romex used so that the proper sized breaker was used.
There had been a few questionable wire gauge things happening from a previous electrician which I corrected.
Installed wired smoke detectors at the same time which was code in the addition.

All with a permit and inspected.
At the time, I was lucky enough to have an electrician friend who lived next door and guided me through the process, and helped me install the new meter box, drop and panel.

Passed inspection with flying colors.
I did a lot of the other work on the addition which involved 2 other permits and inspectors.
I overheard one inspector saying to another "yea, this is fine, overbuilt like everything else." :thumbsup:
 
OBMG74 said:
10 years ago, we had a 1,200 ft addition built onto our house.

I installed a new 200 amp panel and meter box on the addition which became the main breaker panel and ran a huge romex wire (100 amp rated) from it to the old main box in the garage which then became a sub-panel after the electric company moved the drop from it to the new box.

I ran all of the wiring to all of the outlets and lights, including a sub-panel with breakers in the shop.
Took photos of all of the wiring before the drywall went up. That becomes handy when hanging things on a wall, so fasteners don't hit any wiring.

I drew up a map which shows which outlets and lights are on each breaker and it lives on the front panel of the box.
Did the same for the original part of the house, including the gauge romex used so that the proper sized breaker was used.
There had been a few questionable wire gauge things happening from a previous electrician which I corrected.
Installed wired smoke detectors at the same time which was code in the addition.

All with a permit and inspected.
At the time, I was lucky enough to have an electrician friend who lived next door and guided me through the process, and helped me install the new meter box, drop and panel.

Passed inspection with flying colors.
I did a lot of the other work on the addition which involved 2 other permits and inspectors.
I overheard one inspector saying to another "yea, this is fine, overbuilt like everything else." :thumbsup:
Click to expand...
Now that is some good skills to have, especially given the fact that it would cost you a pretty penny to hire someone else to do the work...
 
Sure. Nothing prevents one from going above and beyond Code, as long as the AHJ inspector can determine whatever it is still complies with Code.

Code isn't really about maximum performance or highest efficiency or that sort of thing. Its primary intent, AFAIK, is safety and fire prevention.
 
Most solid state stuff built recently usually does not carry super deadly voltages. Of course you have the 120 volt line which can kill if the grounding is strong enough. The rail or main operating voltage is usually 30 to 70 volts. Tube amps are a different story, 300 and 400 volts are common and can cause severe shocks if your not careful.
 
kwayde said:
Back in the '70's when I was in the Navy working on an old tube communication receiver for NATO in Italy I was doing an alignment and while watching the scope I accidentally touched something I shouldn't have.

One second I was tweaking it, the next I was spread out on the floor a number of feet away. I was confused as to why I was there when I was just sitting at the bench doing an alignment. Took a few seconds to figure it out.

No pain and no memory of the flight. One second I was there, the next I was over here.
Click to expand...
Where I first started working, there was this Doctor. He was prolly in his 40s and had just married an RN in her late 20s (second marriage for both).

Anyhow, they bought a little farmhouse that they were restoring. He went to rewire the barn and turned off the main circuit breaker. He was clipping an old bundle of wires, and sure enough, they were live.

His wife found him dead on the floor, even though he was using large wire clippers with an insulated handle.

That story taught me always to double-check the correct breaker. Using this.
 
Mr Boochie said:
Where I first started working, there was this Doctor. He was prolly in his 40s and had just married an RN in her late 20s (second marriage for both).

Anyhow, they bought a little farmhouse that they were restoring. He went to rewire the barn and turned off the main circuit breaker. He was clipping an old bundle of wires, and sure enough, they were live.

His wife found him dead on the floor, even though he was using large wire clippers with an insulated handle.

That story taught me always to double-check the correct breaker. Using this.
Click to expand...

I wonder if I had stumbled upon the beginnings of how the engineers on Star Trek were able to figure out how to transport people.....
 
cronie said:
Most solid state stuff built recently usually does not carry super deadly voltages. Of course you have the 120 volt line which can kill if the grounding is strong enough. The rail or main operating voltage is usually 30 to 70 volts. Tube amps are a different story, 300 and 400 volts are common and can cause severe shocks if your not careful.
Click to expand...
Largely agree but gotta look out for some types of amps with potent SMPS.

Several I have take the 120V mains through a voltage doubler into a primary capacitor reservoir so you could get sideways with ~340V across a bank of several thousand uf capacitance. Not unlike a tube amp, but with a lot more capacitance than most. And, rail voltages well over +/-100V. One schematic right at hand shows high rail +/-144V.
 
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cronie said:
Most solid state stuff built recently usually does not carry super deadly voltages. Of course you have the 120 volt line which can kill if the grounding is strong enough. The rail or main operating voltage is usually 30 to 70 volts. Tube amps are a different story, 300 and 400 volts are common and can cause severe shocks if your not careful.
Click to expand...
Solid-state amps (especially big ones) can carry lethal current. So, you should still be careful.

:thumbsup:
 
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