E.S. Shield option on reed relays

Discussion in 'General Electronics Chat' started by superduper, Dec 5, 2012.

  1. superduper

    Thread Starter Active Member

    Dec 5, 2010
    I just picked up some NOS DIP reed relays which I plan to use on a project to create a relay array to replace an obsolete 6P3T mechanical switch on an old portable radio.

    The relays in question shows part no: PRME15005AB, GI Clare belgium 46-85. I found a datasheet online for a PRM15005AB by Cotorelay which I presume is a different manufacturer but same replacement part.

    Anyhow, I discovered that the AB suffix suggests this relay has diode and E.S. (shield) option. Can someone shed some light regarding how to use this E.S. shield option?

    Datasheet merely shows:
    A = ES option - pin #9
    B = Diode option - pin #13 is positive.
    AB = Shield and diode option.

    Option B is pretty explanatory. But how is pin #9 used? Tie to ground? Or just ignore?

    Thanks in advance.
  2. KrisBlueNZ


    Oct 17, 2012
    I GUESS it's an electrostatic shield between the coil and the reed switch(es). If it's there, you might as well tie it to circuit ground. If you think there's a chance that the relay's isolation voltage could be exceeded (e.g. during a lightning strike) you might want to bring it out to a separate low-impedance ground.