not another sensing question?

Discussion in 'The Projects Forum' started by tibbles, Aug 6, 2014.

  1. tibbles

    Thread Starter Active Member

    Jun 27, 2008
    fraid so, this time i may be trying to do the impossible,
    im looking or a way of detecting the presence of current through a wire .
    but, and its a big but, it must be completely non invasive,
    the current is around 6 amps,and the voltage 12 volt dc.
    i dont need to measure the current, just wether it present or not.
    i am getting a few - about 6- degrees deflection on a cheap compass,
    not very practical though.
    could use a small coil if it was split, but i suppose that defeats the object of a coil,
    any and all ideas welcome
    thank you
  2. paulktreg

    Distinguished Member

    Jun 2, 2008
    Epoxy a thermistor to the wire and see if you can detect a temperature rise?
  3. MrCarlos

    Active Member

    Jan 2, 2010
    Hello Tibbles

    The DC clamp-on current meter. uses a coil to measure DC Current.
    The secret is that circulate AC signal through the coil which is wound on a ferrite core.
    As soon as a DC current to flow. alter the flow of AC current; this change is converted to a measure that could be displayed on a galvanometer or a digital display.

    Another method is to use a device known as Hall effect.
    ISHWAR Answer, 4 years ago, in YAHOO

    The Hall effect type digital clamp meter is able to measure both DC and AC
    The Hall effect is the production of a voltage difference (the Hall voltage) across an electrical conductor, transverse to an electric current in the conductor and a magnetic field perpendicular to the current. The Hall coefficient is defined as the ratio of the induced electric field to the product of the current density and the applied magnetic field. It is a characteristic of the material from which the conductor is made, as its value depends on the type, number, and properties of the charge carriers that constitute the current.

    You can get the ferrite core from an old PC power supply.
    The Hall effect device must investigate the price of it.
  4. DerStrom8

    Well-Known Member

    Feb 20, 2011