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Heaters wired in parallel

  1. Aug 30, 2010 #1
    I have a circuit that has two 10watt heaters and one 20watt heater all wired in parallel and hooked up to a dc power supply.

    the heaters are kapton flexible heaters made by Omega:
    the manual for these can be found here: http://www.omega.com/manuals/manualpdf/M1249.pdf

    these heaters are adheared to solid copper and i would like to provide the correct voltage or current. The manual specifies the voltage to be 28 volts, but it does not say that this is the maximum voltage or operating voltage, or what. Does this mean that i should apply 28 volts to the power supply? What happens if I apply more or less? I don't want to damage these heaters. Any help would be great.
  2. jcsd
  3. Aug 31, 2010 #2
    It does say:

    "DO NOT operate heaters at a voltage higher than the specified or
    rated voltage."

    So I think any voltage up to 28VDC will be OK. If you apply a higher voltage they might overheat and worst case catch fire!

    Be sure to follow all the points on page 3 in the manual.
  4. Aug 31, 2010 #3
    If they are resistive (I'm too lazy to follow your link) they should work at lower voltage and just produce less heat. The previous warning about over voltage should be heeded for safety and longevity reasons.

    At 28 volts a 10W heater will draw .35 amps (P = IE ... the easiest Ohms law to remember). Your combination of three in parallel dissipates 40W and uses about 1.5A.
  5. Aug 31, 2010 #4


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    You need to get a temperature controller and a sensor for best performance.
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