Cathode of a resistor

Discussion in 'General Electronics Chat' started by togbott, Jul 31, 2013.

  1. togbott

    Thread Starter New Member

    Nov 20, 2011
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    In the book, "Getting Started in Electronics" there is one presentation implying, but not outright declaring, that the cathode portion(?) of a resistor is the side with color bands.

    With a wire-wound resistor, there are no color bands, simply printed text declaring functionality. Can I assume the left-most edge, when the text is readable is the cathode portion?

    I'm ultimately trying to determine which end of the wire-wound resistor is clock-wise or counter-clock-wise.
     
  2. MrChips

    Moderator

    Oct 2, 2009
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    Resistors are not polarized. There is no cathode.
     
  3. togbott

    Thread Starter New Member

    Nov 20, 2011
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    I thought the terms anode and cathode were used to note the incoming and outgoing current. My mistake.

    I'm still looking for a coil direction test of a wire-wound resistor.
     
  4. Ramussons

    Active Member

    May 3, 2013
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    Resistors are unipolar devices and the current flow can be in any direction.

    If you want to do a "coil direction test of a wire-wound resistor" one way is to send a current thru' it and use a "magnetic compass" to identify North and South poles, apply the Right Hand Rule to get the coil winding direction.

    Ramesh
     
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  5. Ron H

    AAC Fanatic!

    Apr 14, 2005
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    Why do you want to know this?
     
  6. togbott

    Thread Starter New Member

    Nov 20, 2011
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    To personally experience the difference (if any) between the two forms of coiling.
     
  7. tracecom

    AAC Fanatic!

    Apr 16, 2010
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    I believe that some wire-wound resistors have the coil direction reversed one or more times in order to minimize inductance.
     
  8. wayneh

    Expert

    Sep 9, 2010
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    For what it's worth, a right-handed helix is still right-handed when you turn it around. You need to find both right and left helices if you really want to be thorough.

    I'll be amazed if you can demonstrate any detectable difference from resistor orientation. They do not have cathodes or polarity and I'd be willing to bet the markings are applied randomly in manufacture.
     
  9. Ron H

    AAC Fanatic!

    Apr 14, 2005
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    Some wirewound resistors are wound to be noninductive.
     
  10. Wendy

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    Mar 24, 2008
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