Double pole double throw switch

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I had a test question and I was unsure of the answer, I am hoping someone can answer it.

The question read, what is a double pole double throw switch?
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
This is a DPDT knife switch. Double Pole, Double Throw:

26-790.jpg

See how it relates to the DPDT switch here?:

switch_symbols.gif
 

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4 way switch

4 way switch

This is a DPDT knife switch. Double Pole, Double Throw:

26-790.jpg

See how it relates to the DPDT switch here?:

switch_symbols.gif

Sorry to say this picture is a double pole single throw switch. The answer to the question is a 4 way switch is a double ploe double throw switch. The number of throws is based on the individual poles. Always look at one pole at a time and determine how many positions there are. If you can only complete one path per pole it is single throw, if you can complete two paths per pole it is double throw and if you can complete more than two throws per pole it is a multiple throw switch. A 4 way switch can complete two paths per pole and is therefore a 2 pole 2 throws per pole switch (DPDT).

This is a fundamental electrical theory question on electrician exams.

http://en.wikipedia.org/wiki/File:DPDT-symbol.svg

http://en.wikipedia.org/wiki/File:4wayswitch.svg
 

spacebar

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Sorry correction; the picture was correctly identified as a DPDT but the rest of my post was correct. It's a 4 way switch there looking for on the test.
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
It's a 4 way switch there looking for on the test.
If you wire the diagonally-opposite terminals together, forming a reversing switch, then you would have a 4-way switch, thus:

elec11.gif


Note that a DPDT has six terminals, but a 4-way only has four.
 

ohmhead

Senior Member
Location
ORLANDO FLA
Well its a double throw 4 pole center fed top to bottom manual transfer switch kinda does the same thing as 2 pole double throw switch with 2 extra poles dont be so picky

































That would be a quadruple-pole. :D[/QUOTE]
 
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