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How do I calculate Switch current capacity needed
Last Post 28 May 2012 01:52 PM by Niel. 1 Replies.
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David1062
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Posts:1

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25 May 2012 01:22 PM
    How do I calculate the needed current rating on an on/off switch used to power 12V or 24V G4 Halogen bulbs with either a 12VAC, 24VAC or 12VDC and 24VDC power source.
    Say I wanted to operate 2, 35watt G4 Halogen bulbs using 12VDC power. How many amps would the switch need to be rated for. And what would it need to be rated for if it was a 24VDC system or AC system?
    Is there a formula so no matter the wattage I can figure it out?
    Thank you,
    David
    Niel
    Basic Member
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    Posts:193

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    28 May 2012 01:52 PM
    David:

    Remember Power [Watts] is Volts x Amps.

    or for your application

    Amps = Watts / Volts

    You can use this in any application to calculate the current, but remember when determining the ratings for your switch you need to do more than evaluate the steady state needs of your application you need to look at the transients which will occur when the switch is turned on and off.

    Niel Leon
    engineering.com
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