on and off switch?

Discussion in 'General Electronics Chat' started by AXmichigan, Jul 18, 2009.

  1. AXmichigan

    Thread Starter Member

    Jun 17, 2009
    hey guys
    thank you all for the help thusfar
    becuase of you guys i have been able to successfully progress in my project :cool:

    so now i had another idea
    i designed my project to be battery powered, of which i was going to disconnect and reconnect it to not use it
    but that seemed awful
    now i realized i could put an on and off switch to simply turn it on and off,
    i think the SPST would be good right? it wont limit the power to the circuit right?

    how do i connect it and the switch & battery to the circuit?

    and i found this one
    (the switch has 3 slots on bottom according to its datasheet, the power would be battery, ground would be ground... but the middle says ADC... it doesnt convert it voltage or anything does it??)

    would it be okay?
    Last edited: Jul 18, 2009
  2. SgtWookie


    Jul 17, 2007
    Actually, the switch has three spade-type terminals:
    Power, ACC, Ground
    Power goes to your +V supply (battery + terminal).
    ACC is where you would connect the +V to your project.
    Ground gets connected to your battery - terminal. The only purpose of the Ground terminal is to provide a current path for the red LED in the switch handle; it will glow when you turn the switch on.

    Make certain that you have a suitably rated fuse between the battery and the switch. Otherwise, if there is a fault in your project or the switch wiring, you may suffer a catastrophic melt-down.
  3. AXmichigan

    Thread Starter Member

    Jun 17, 2009
    hey thanks for the help
    so just to double check, i connect both parts of the battery to the switch?
    with + and - to the power and ground respectively?

    what do you mean a suitably rated fused? im not sure what a fuse is really, especially not one that needs to be rated.. :(

    i was planning on just connecting the battery to the swtich and to the board
    do i need an additional part?

    so i connect the Acc part to the +V on the board, but what do i connect to the ground since the battery ground is to the switch itself?

    sorry for the questions, but thanks!
  4. SgtWookie


    Jul 17, 2007
    Connect the battery positive terminal via a fuse to the Power terminal.
    Connect the battery negative terminal to the Ground terminal.
    Power your project via the ACC terminal.

    How much current do you expect that your project will require?

    If you expect less than 1A, then use a 1A or 2A fuse. If you expect it to draw 3A, then use a 5A fuse. The point here is to protect the circuitry and wiring; in case something goes wrong, the fuse will burn up instead of the circuit and wiring.

    You will need a fuse holder for the fuse.

    The board ground needs to be connected to the battery too. If it makes it easier, you could run battery ground straight to your project board, and then run a small wire back to the switch to provide a ground for the LED. It won't require much current handling capacity; perhaps 20mA.
  5. AXmichigan

    Thread Starter Member

    Jun 17, 2009
    hey im sorry
    this sound a little more complicated than i would want
    that being said, ive decided to go retro a bit, and go with this on-off switch

    what do you think?
    my whole thing is not very large or highly powered, it will be a simple 9V battery that runs to it and turns the whole thing on and off
    i am not sure if it could fit the contact voltage required

    how would i connect this one?
    (manual: http://spec.e-switch.com/P-J/P300008.pdf)
    there is only two pins on it, so i know its different
    is it as simple as the battery v+ to the out side pin, and that inside pin to the V+ on the board, and I ground the v- of the battery?

    sorry for the questions, i do really appreciate it
  6. SgtWookie


    Jul 17, 2007
    Sure, that would work.
    Oh, just a 9v battery? Well, you won't need a fuse then. The switch you've selected is maximum overkill, but it should last just about forever ;)

    Yes, that's how you'd connect it. Questions are fine - if you're not sure of something, it's better to ask than make a mistake and burn something up.
  7. AXmichigan

    Thread Starter Member

    Jun 17, 2009
    Thank you so much :cool: