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Magnetic Particle Testing

Magnetic Particle Testing

Magnetic Particle Testing

When using the Direct Head method to create a field around a test piece, why does electrocution not come into play if piece is touched?  HIGH Amperage/Low Voltage?  My basic Physics have disowned me!

RE: Magnetic Particle Testing

I'm not familiar with the method but you said high amperage, low voltage.  

Start with low voltage.
The metal has very low resistance.
You have very high resistance.

Place yourself in paralell with the metal.
A very high current in the metal, a very low current in you.

People routinely handle batteries at low voltages 1.5volt, 9 volt etc with no fear of electrocution.  I believe you need to get up to around 40 volt to develop a current high enough to stop your heart and that only in very ideal conditions like you are handling the electricity in a rainstorm.

Sorry, I didn't mean to in any way diminish the safety significance of electric power.  At low voltage less than 10 volts for example it would be very difficult to figure out a way to hurt yourself.

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RE: Magnetic Particle Testing

I used to hold magents in pulse coils with my fingers and hit them with 50,000A at 500V.  There is no significant voltage induced either in the magnet or your hand.  But you had better pray if one of the coil leads is damaged.

= = = = = = = = = = = = = = = = = = = =
Corrosion never sleeps, but it can be managed.

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