help please.. using the parallel port to turn on a solid state relay..

Discussion in 'Homework Help' started by blooandy, Jan 3, 2008.

  1. blooandy

    Thread Starter New Member

    Jan 3, 2008
  2. mrmeval

    Distinguished Member

    Jun 30, 2006
    5v from a parallel port is perfect as the SSR you chose needs very little current on the DC side. But here's some parport info in case it's non-standard in some odd way.

    In fact I have an OMRON that draws so little I could piggy back an LED and it still worked.

    Should be 3-32 volts on the DC side and for the AC your line / mains voltage and rated at the max current of both devices + 25 percent. so 100 amp would need 125 amp etc

    There are calculations in the documentation that tell you how to figure out what resistor to use if you use a higher voltage than 3VDC for the control voltage. Damn good specs on those SSRs

    Pay attention to the heatsink requirements. Pay attention to the need for a snubber.