Resistor lead diameter grumble

Discussion in 'General Electronics Chat' started by tracecom, Jun 22, 2013.

  1. tracecom

    Thread Starter AAC Fanatic!

    Apr 16, 2010
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    I received an order today from a well known supplier. Some of the 1/4w resistors have what I consider to be "standard" lead diameter, i.e., ≈ .021", but others have what I consider to be cheap lead diameter, i.e., ≈ .013". The thinner ones are also shorter. Functionally, I suppose it doesn't matter (except for solderless breadboard use), but it "bugs" me.

    Would anyone else be bothered by this?
     
  2. #12

    Expert

    Nov 30, 2010
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    Yes. The fatitude of the wire is a key factor in the thermodynamics.
     
  3. tracecom

    Thread Starter AAC Fanatic!

    Apr 16, 2010
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    Well, that sent me to Google. :)
     
  4. #12

    Expert

    Nov 30, 2010
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    I thought a country boy like you would know that without any hesitation :D

    I only meant, "diameter", not what the google page says.
    (I didn't even know about the google definition.)

    Anyway, the mass of the connecting wire is a primary exit for heat.
     
  5. tracecom

    Thread Starter AAC Fanatic!

    Apr 16, 2010
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    Oh, so you were serious; there is a downside to the skinny wires.
     
  6. #12

    Expert

    Nov 30, 2010
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    Sorry. The silly button got away from me.:D
     
  7. THE_RB

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    Feb 11, 2008
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    I would not stress over it. They are just saving metal costs on what are basically obsolete parts now apart from hobby use.

    A 1/4W resistor would not be a good choice if you need to push the heat dissipation spec anyway, I would use 400mW metal film which are about the same package and mount size.
     
  8. Dr.killjoy

    Well-Known Member

    Apr 28, 2013
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  9. tubeguy

    Well-Known Member

    Nov 3, 2012
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    Yes, it bugs me.

    I also got some shorter-than-normal resistors which were a pain to use recently when they didn't reach as far as the original part.
    I received some T0-220 regulators where the 7815's had a tab that was
    about 1/2 the normal thickness. That was also a BIGGER pain 'cause the
    original shoulder washer didn't work without a slight modification.

    Oh Well...:)
     
  10. Ron H

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    Apr 14, 2005
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    Great word!:D
    I believe fatosity is another acceptable term for wire diameter.;)
     
  11. Duane P Wetick

    Active Member

    Apr 23, 2009
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    This brings to mind a GE locomotive over-reaction when a locomotive would not start for world dignitaries all because of the failure of a 3 watt resistor. When I was shown the offending component, it was obvious (at least to me), the resistor maker decided to economize the leadouts due to the cost of copper and used a smaller wire size. Wire fatigue (or the other word) caused the problem so all locomotive resistors had to be 100% tested after this event. I think they went to fatter power resistor leadouts after this.

    Cheers, DPW [Everything has limitations...and I hate limitations.]
     
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