12v UPS relays Trigger, 1 ~ 11v no trigger

Discussion in 'General Electronics Chat' started by Jacquesl, Aug 24, 2007.

  1. Jacquesl

    Jacquesl Thread Starter Member

    Dec 9, 2006

    I’m busy with some UPS circuit and I need it to switch a couple of relays on then the power is back.



    Can I replace the triac with a transistor because I don’t want to let the relays on until the power is down,

    I basically want a easy method to trigger a couple of relays then the mains is back, currently I’m using a 10volt reformer on a 12v relay and if the mains drop the relay drop very fast, but the transformer is to small for 3 relays and then using 3 relays I hear a buzz sounds because it probably under power, in my circuit I have a regulated power supply and a small crap 10 – 11volt power supply just to do the relay work and the regulated power supply with huge caps is for the timer section and some other components

    Purpose needed for:

    1 ~ 11 volt - no trigger
    12 volt - trigger

Similar Threads
Forum Title Date
General Electronics Chat HVAC Issue with Relays Apr 4, 2015
General Electronics Chat duty rating of those auto cube 40 amp 12vdc relays? Mar 20, 2015
General Electronics Chat Adjustable delay switching of two relays alternately Mar 4, 2015
General Electronics Chat Replace a buzzing relays Dec 3, 2014
General Electronics Chat controlling 1 or 2 motors with 2 relays Nov 19, 2014

Share This Page