sense resistor coupling

Discussion in 'General Electronics Chat' started by gehan_s, Nov 23, 2012.

  1. gehan_s

    Thread Starter Member

    Sep 17, 2012
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    hey all,

    i have a 0R5 sense resistor in the neutral side of the AC mains. i need to isolate this input and feed it to a PIC microcontroller. how do i do this???? (there is about a maximum of 4A rms curent flowing through it)

    thanks !!!!!!!!!!!!!!!
     
  2. ScottWang

    Moderator

    Aug 23, 2012
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  3. spinnaker

    AAC Fanatic!

    Oct 29, 2009
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    Look at a Hall Effect Sensor.
     
  4. gehan_s

    Thread Starter Member

    Sep 17, 2012
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    Thank you ScottWang and spinnaker. I did consider the Hall Effect Sensor earlier. Can you please tell me why you think the series resistor is a bad idea ? Is the Hall Effect Sensor more accurate than using a series resistor ?
     
  5. spinnaker

    AAC Fanatic!

    Oct 29, 2009
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    I thought that was obvious.

    You would like to go on living and / or have you house not catch on fire right?
     
  6. ErnieM

    AAC Fanatic!

    Apr 24, 2011
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    One thing usually overlooked by those using this scheme is you are intentionally breaking the safety bond between neutral and ground by that very same sense resistor.

    Thus your entire unit is less safe then one observing a proper neutral connection.
     
  7. Jaguarjoe

    Active Member

    Apr 7, 2010
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    How about a current transformer. No disrupted neutrals.
     
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