Relay Vs Flash capacitors - will it blow?

Discussion in 'The Projects Forum' started by AdamH, Jul 17, 2012.

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  1. AdamH

    Thread Starter New Member

    Jul 17, 2012
    This is part of a coilgun project I am working on.

    So i have an SPST relay rated at 2A, which can be switched by a signal from a 9v battery. The 'higher current' it will be taking is from a photoflash capacitor of capacitance 80uF, rated at 330v.

    My question is, provided the capacitor discharges in 4.4ms (from my calculations) will it blow the relay?

    I am confused because there are two ways of looking at it:
    1) I've calculated that if this discharge continued for one second (which is what current measures - coulombs per second) the capacitor will discharge 6 Amps through the relay, thereby blowing it.

    2) HOWEVER, given it can only hold 2.64x10^-2 coulombs and is (for all calculations) fully discharged after 4.4ms, in the full second after it begins discharging the current which has passed through the relay is only 2.64x10^-2 Amps.

    So which is correct?? :confused:
    Last edited: Jul 17, 2012
  2. Bernard

    AAC Fanatic!

    Aug 7, 2008
    Depends on type of relay contacts, if rated for high V , 2A rating will probably carry pulsed overload with no problem. " coil gun" will most likley bring " CLOSED" to your post.
  3. bertus


    Apr 5, 2008

    I am closing this thread as it violates AAC policy and/or safety issues.

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    • Any kind of over-unity devices and systems
    • Automotive modifications
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    • LEDs to mains
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