SCR phase control

Discussion in 'General Electronics Chat' started by damonj, Jan 28, 2010.

  1. damonj

    Thread Starter New Member

    Jan 28, 2010
    I've got an old welder that uses two SCRs for current control. I'm trying to re-engineer the electronics for the scr control, I was looking at the 555 timer for this but then I learned about the TCA785. Anybody have any experience with this? Are there other ICs out there that might be a better choice? The two SCRs control 15 volts each and are rated for up to 110 amps. I can't find a datasheet for the SCRs but my calculations show that gate current needs to be as low as 20 ma, but a little higher would probably be desireable. I can provide a drawing of what I have if need be.
  2. radiohead

    Distinguished Member

    May 28, 2009