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how to calculate this?

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  • how to calculate this?

    If I have 8 units of 7 x10 LED Lights...

    - Per Unit PAR CAN is 7x10w = 70w

    - 8 Units PAR CAN - 70w x 8 = 560w

    Malaysia uses 230/240v...


    So 560w divide by 230 =2.43ampere ?

    If this formula correct to calculate how many amperes my 8 Par Cans will draw?

    I have posted this topic in Lighting forum too. I wanna see if I can get the accurate answer from both sides :-D


  • #2
    Read the manual on this one, there's also power supply draw too. So little draw to me says put it on a circuit with not much already going on (like back line).
    <div class="signaturecontainer"><a href="http://www.rock-bot.com" target="_blank">www.rock-bot.com</a><br />
    Live-Band-Karaoke<br />
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    bassist and sound reinforcement</div>

    Comment


    • Bugzie
      Bugzie commented
      Editing a comment

      Google "Ohm's law"


  • #3

    Looks about right to me.

    Thanks,
    Bill Cronheim
    Enterainment Systems Corporation
    Back stage since 1973

    Comment


    • #4

      stunningbabe wrote:

      So 560w divide by 230 =2.43ampere ?

      Is this formula correct to calculate how many amperes my 8 Par Cans will draw?

      I'll suggest:  Yes, the formula (computation) is correct.  The result (2.43A) is as correct as the specifications of the lighting fixtures.  I believe the appropriate term for the result of your computation would be "par value".

      If it matters: you could verify the actual current draw with an induction amp meter (read and follow instructions of the meter).  Chances are it wouldn't matter if the actual draw was 10% or even 20% more-or-less than what the computation suggests.

      I need to catch up with those guys, for I am their leader.

      Comment


      • #5

        You got it.

        Comment


        • stunningbabe
          stunningbabe commented
          Editing a comment

          Thank you to all the fine gentlemen here.


      • #6
        Power amp is not as easy since there are multiple conditions involved. Generally it's probably close to what is listed in the specs for 1/8 power consumption at whatever impedance load you are using

        Comment


        • #7
          That's a good tip, I'll keep that one on file

          Comment


          • stunningbabe
            stunningbabe commented
            Editing a comment

            Thx guys.

             

            Audiopile...yes you are right. I am scared to trip the breaker.


        • #8
          What kind of amp? Class AB? G/H? D?

          Is this total power of per channel?

          How is this power rated? DB

          RMS? Peak? Behringer?

          Comment


          • stunningbabe
            stunningbabe commented
            Editing a comment

            What kind of amp? Class AB? G/H? D?

            Is this total power of per channel?

            How is this power rated? DB

            RMS? Peak? Behringer?

             

            WOW! so many factors involved? OMG!

             

             

             

             


        • #9
          You guys are all way off base in your estimates.

          For a class d amp, 1000 watts rms (really) per channel is about 85% efficient so 2000 watts x 1.15 = 2300 watts x some factor between 0.125 and 0.250 gives average audio power at 85% efficiency and divide this by 230 v to get average current at 230v at 8 ohms

          There will be a different average power consumption at different load impedances based on the amplifiers rated load capacity.

          If the amp is rated at peak power, the power delivered and consumed will be derated by 50% because of the math difference.

          Comment


          • stunningbabe
            stunningbabe commented
            Editing a comment

            Once again...agedhorse has managed to answer my question in depth. Now...if only I can understand what he said " id="smiley" src="https://guitarcenter.i.lithium.com/i/smilies/16x16_smiley-.png" alt=":smiley:" title="Smiley Very Happy" /> I feel so stupid sometimes as I cant understand some of the things he said...due to my poor English .png" alt=":smileysad:" title="Smiley Sad" />


          • Okie4Cards
            Okie4Cards commented
            Editing a comment

            At 230V, the QSC PL340 is rated at 7A current draw with typical music program material with occasional clipping.

             

            This is straight from their spec.

             

            I have specified AC requirements for many projects. I use this spec to determine my AC requirements.

             


            agedhorse wrote:
            You guys are all way off base in your estimates.

            For a class d amp, 1000 watts rms (really) per channel is about 85% efficient so 2000 watts x 1.15 = 2300 watts x some factor between 0.125 and 0.250 gives average audio power at 85% efficiency and divide this by 230 v to get average current at 230v at 8 ohms

            There will be a different average power consumption at different load impedances based on the amplifiers rated load capacity.

            If the amp is rated at peak power, the power delivered and consumed will be derated by 50% because of the math difference.


            Please show me how this is inaccurate. 


          • Gregidon
            Gregidon commented
            Editing a comment

            agedhorse wrote:
            You guys are all way off base in your estimates.

            For a class d amp, 1000 watts rms (really) per channel is about 85% efficient so 2000 watts x 1.15 = 2300 watts x some factor between 0.125 and 0.250 gives average audio power at 85% efficiency and divide this by 230 v to get average current at 230v at 8 ohms

            There will be a different average power consumption at different load impedances based on the amplifiers rated load capacity.

            If the amp is rated at peak power, the power delivered and consumed will be derated by 50% because of the math difference.

            Not sure I agree with "you guys are all way off base". My estimate comes in pretty darn close to yours (though you explained the specifics a little more clearly).


        • #10
          How many of what do you want to plug into what type of circuit at the same time.

          NO SIGNATURE FOR YOU!!

          Comment



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