Triac based heater control

Discussion in 'The Projects Forum' started by picstudent, Nov 8, 2010.

  1. picstudent

    Thread Starter Well-Known Member

    Feb 3, 2009
    I need to control a 500W cartridge type heater as a part of PID temperature control.
    AS far as I know Phase control and Pulse skip modulation or burst mode control are the available options.

    Which is the best mode for heater control?
    At this wattage, Triacs or Solid state relays, which are more feasible?
  2. Kermit2

    AAC Fanatic!

    Feb 5, 2010

    I would not use a relay, regular, or solid state for continuous on/off operation. They have a finite mechanical life and will fail eventually due to exceeding the operational life of the on/off mechanism. PWM rates are 100's to 10,000's of cycles per second. The relay would be dead in a day or a few weeks at that freq.

    Use simple SCR's.
    picstudent likes this.
  3. Tahmid

    Active Member

    Jul 2, 2008
    At 500W switching application for power control, the way to go is solid-state. You can use both phase-angle control and pulse skipping modulation. 500W power is not very high, and here triac can be used with no problem, but SCR is safer no matter what, not to say that triacs wouldn't do the job. I think upto a kW, triacs are fine, but SCRs are just safer because of no chance of faulty triggering or misfiring.

    Hope this helps.
    picstudent likes this.