Randall Amp Problems

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JoeCon
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Re: Randall Amp Problems

Post by JoeCon »

Jana

Carl Sagan??
In theory, theory is the same as practice. In practice it's different.
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Structo
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Re: Randall Amp Problems

Post by Structo »

Getting a shock on one hand hurts enough without getting current in one hand, passing through your chest cavity to the other hand.

Guess what?

Your heart is in the middle of your two hands.

I was taught that DC was worse than AC when getting shocked because the voltage and current are well above zero, which can lock your muscles and prevent you from releasing your hands.

AC at 60Hz goes to zero every half cycle which may result you being able to let go.

When I was in high school electronics class, our instructor told us that.
During my time there we had high bench top voltage DC power supplies for doing experiments.
He said that all you need to stop your heart was around 50ma, when it travels up both arms.

I was working with 400v DC one day and my hand slipped, and I got bit.
I was sitting on a bar style chair and it blew me backwards off the stool.
It was only on my right hand as he had instructed us to only use one hand when probing the circuit.
I am no expert and I am fine with a discussion on this, as I am not a PHD or have any other letters after my name.:D

What say you?
Tom

Don't let that smoke out!
matt h
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Re: Randall Amp Problems

Post by matt h »

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johnnyreece
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Re: Randall Amp Problems

Post by johnnyreece »

I say I'm not sticking my hand in an electrical device without proper precautions or without knowing what I'm touching. I don't care if there's a 99% chance it won't kill me; 1% is still too much of a chance to not be careful. I know...I'm no fun...
Zippy
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Re: Randall Amp Problems

Post by Zippy »

matt h wrote:
Structo wrote:What say you?
You may want to read the links I provided (the wiki addresses this in the first body paragraph).

AC has a lower "let go" threshhold insofar as current is concerned. This causes (or may cause) clamping onto the object shocking you, which causes longer exposure, which causes more current to flow through you, which makes fibrillation more likely. Death-i-er.

DC, on the other hand, is more likely to pack a higher wallop when you get hit (getting blown back in your chair) at a point before fibrillation is as likely.

They're both dangerous, better to err on the side of caution, yada yada yada.
Thank you, Matt.

That reflects my professional training as well. One will cook you, the other puts your heart in an indeterminate state (fillibration). Which way would you rather die? Knowing that it can be avoided, one can be prudent and avoid the issues.
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Structo
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Re: Randall Amp Problems

Post by Structo »

Thanks guys, that helps.

Anybody ever get shocked when working on a lawn mower?
(coil, spark plug)

Man, that can make your arm ache for some time. :shock:
Tom

Don't let that smoke out!
matt h
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Re: Randall Amp Problems

Post by matt h »

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C Moore
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Re: Randall Amp Problems

Post by C Moore »

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