Magnetic data transfer through thin steel plate

Discussion in 'General Electronics Chat' started by Zed Zamorin, Jun 4, 2016.

  1. Zed Zamorin

    Thread Starter New Member

    Jun 4, 2016
    Is it possible to transfer data between two magnetic coils separated by thin steel metallic plate (2mm)? Or does the magnetic field gets diminished by the plate?
  2. #12


    Nov 30, 2010
    Thin steel plates are an excellent way to stop magnetic fields from passing through a place.
    This is like asking if a sheet of glass is a good thing to send water through.
  3. DickCappels


    Aug 21, 2008
    Sure if the metal plate is not magnetic (aluminum, copper, etc.) and the data rate is low enough that there is not a problem with eddy currents.

    It can be done with magnetic materials if the metal is thin and there is enough of magnetic field is able to significantly change permeability (as in saturate) of the metal.
  4. #12


    Nov 30, 2010
    Looks like a difficult job to me.
    In applications of intentional magnetic shielding 0.079 inches is not, "thin". 0.0079 inches is thin.;)
  5. MrAl

    AAC Fanatic!

    Jun 17, 2014

    The thickness is 2mm, but what is the length and width of the plate?

    Very sorry guys, but this is possible.

    The plate is a little thick, but once the steel is saturated it's almost not there at all anymore. This means you can detect the magnetic field on the other side of the plate if the magnetic field is strong enough. In a thin plate, even wide and long, you'll detect the field on the other side as long as the transmitting coil can produce enough of a field to satisfy whatever kind of sensor you are using. You may be limited in frequency though, but some experimentation with what you actually have there would tell you exactly what you need to know: how strong of a field you need.
    So you see it is greatly dependent on how sensitive you can make the sensor, or coil if you use another coil as the pickup sensor.
    Also, the transmit coil should have a core, and should be placed right up against the plate, and also the receive coil should be right up against the plate too.
    If you intend to transmit energy this way you may loose a lot of coupling in the plate and due to the frequency the plate will absorb some energy and get warmer, but again it depends how wide and long the plate is not just the thickness. Signals however will get through.
    Last edited: Jun 4, 2016
  6. crutschow


    Mar 14, 2008
    If you can make the plate out of non-magnetic stainless steel, then it's also simple to do.
    DickCappels likes this.
  7. wayneh


    Sep 9, 2010
    It's also simple to drill a hole. ;)
    #12, DickCappels and ErnieM like this.