s wayne cook
Member
- Location
- Virginia
The NEC Handbook makes mention of motor overload protection provided by bimetalic elements or "eutectic material". What is an example of eutectic material?
Wayne Cook
Wayne Cook
Definition Needed!
- Thread starter s wayne cook
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s wayne cook
Member
- Location
- Virginia
Re: Definition Needed!
That's it? Just something with an element that melts? A one shot deal?
That's it? Just something with an element that melts? A one shot deal?
- Location
- Illinois
- Occupation
- retired electrician
Re: Definition Needed!
Wayne,
It is not a one-shot deal. Look at the overload heater, if it has a gear on it or an arm that pushes against a gear in the overload relay it is a eutectic heater. These are also known as "melting alloy heaters". When the current produces enough heat to melt this material, it permits the gear to turn and trip the overload relay. When the metal cools and solidifies again you can reset the overload relay. The first page of this Square D document has a picture of a 'melting alloy overload relay"
Don
Wayne,
It is not a one-shot deal. Look at the overload heater, if it has a gear on it or an arm that pushes against a gear in the overload relay it is a eutectic heater. These are also known as "melting alloy heaters". When the current produces enough heat to melt this material, it permits the gear to turn and trip the overload relay. When the metal cools and solidifies again you can reset the overload relay. The first page of this Square D document has a picture of a 'melting alloy overload relay"
Don
s wayne cook
Member
- Location
- Virginia
Re: Definition Needed!
Thanks Don, the amazing thing is that the metal can go through many cycles of melting and solidifying and still, a.) remain in place, and b.) maintain melting properties that remain accurate.
But I've probably experienced no more failures with this type, than with any other type.
And so, that's what eutectic motor OCP is?
Tonight I learned something. Thanks again,
Wayne
Thanks Don, the amazing thing is that the metal can go through many cycles of melting and solidifying and still, a.) remain in place, and b.) maintain melting properties that remain accurate.
But I've probably experienced no more failures with this type, than with any other type.
And so, that's what eutectic motor OCP is?
Tonight I learned something. Thanks again,
Wayne
- Location
- Lockport, IL
- Occupation
- Semi-Retired Electrical Engineer
Re: Definition Needed!
Combine two metals and thereby create a new metal. The result will have some melting point (i.e., a temperature at which the combined new metal will melt). Change the metal compositions (add a bit more of this, a bit less of that), and you will get a different melting point. The composition that gives the lowest melting point is called the ?eutectic combination.? (My source is the ?McGraw-Hill Dictionary of Scientific and Technical Terms,? and what very little my mind retains of the metallurgy course I had to take in college.)
Combine two metals and thereby create a new metal. The result will have some melting point (i.e., a temperature at which the combined new metal will melt). Change the metal compositions (add a bit more of this, a bit less of that), and you will get a different melting point. The composition that gives the lowest melting point is called the ?eutectic combination.? (My source is the ?McGraw-Hill Dictionary of Scientific and Technical Terms,? and what very little my mind retains of the metallurgy course I had to take in college.)
charlie
Senior Member
- Location
- Indianapolis
Re: Definition Needed!
Charlie, I'll bet that is what wood's metal is all about. That is an alloy that has about 1/2 bismuth along with tin, lead, and cadmium that melts at about 160 F and is used (or used to be used) in sprinkler heads. We used to play with it in chemistry class by melting it in boiling water. Now with a show of hands, who really gives a . . .
Charlie, I'll bet that is what wood's metal is all about. That is an alloy that has about 1/2 bismuth along with tin, lead, and cadmium that melts at about 160 F and is used (or used to be used) in sprinkler heads. We used to play with it in chemistry class by melting it in boiling water. Now with a show of hands, who really gives a . . .
s wayne cook
Member
- Location
- Virginia
Re: Definition Needed!
Thanks guys, now if one of my students ask me what it is I won't look like a total idiot.
Thanks again, Wayne
Thanks guys, now if one of my students ask me what it is I won't look like a total idiot.
Thanks again, Wayne
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