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  • May 14, 2009, 03:44 PM
    brett1trout
    Eletrical & lighting
    How do you wire a series of outlets that can be shut off ( as an emergency ) with the switc of a swith or a push of a button ( DEAD MAN SWITCH )
  • May 14, 2009, 03:55 PM
    Stratmando

    If that serious, You could actually have a push or pull switch at each outlet, so when any are pressed, all will be disconnected.
    Hopefully HKstroud will see this, he does drawings regularly. My scanner is down, wold have to draw out and take a picture. Will do tomorrow if one not provided by then.
  • May 14, 2009, 07:04 PM
    stanfortyman
    You would just wire a typical switch in series with the hot in a box before the receptacles. Then just wire the receptacles as you normally would.
  • May 14, 2009, 08:06 PM
    hkstroud
    2 Attachment(s)

    If I understand this question correctly it is "How do I wire an emergency cut off switch for a series of outlets"?

    Basically this would be wired like any other switched outlet. The switch could be a toggle switch with an "On and an Off". It could be an Push type switch that is normally "ON", that is the contact points are normally close and "Off" when pushed. A "Panic" button. Either way the switch should be rated for the maximum amperage of the circuit. Wiring would be the same for either switch. If you have difficulty locating a "Panic" type switch you might look at after market cut off switch for table saws. There are several that are designed to be cut off by bumping with your knee. These should also be rated at 20 or more amps.
  • May 14, 2009, 09:37 PM
    andrewc24301
    Don't forget to make sure the switch is rated for the amps that the circuit may be pulling under a full load. Get a heavy duty switch if possible. If you require a smaller light duty switch, you may want to inplement a contactor.
  • May 15, 2009, 01:27 AM
    ohb0b
    What is the application? Is this for a residence?

    When you say "Deadman's" switch, I am assuming you mean momentary contact pushbutton.

    This requires an industrial type 3-wire start/stop circuit with a relay that is rated for the load, or a push/pull button like you see as an emergency shut-off for the gas pumps at the 7-Eleven.

    You could do it, but it is more cost efficient to simply switch the receptacles off with a toggle. If this is a home installation, you would have an easier time getting it past the electrical inspector.
  • May 15, 2009, 04:32 AM
    Stratmando

    HK, can you provide a drawing with his "deadmans" next to each receptacle, that will shut off supply to all recepticles for poster? Thanks
  • May 15, 2009, 10:58 AM
    ohb0b
    Quote:

    Originally Posted by Stratmando View Post
    HK, can you provide a drawing with his "deadmans" next to each recepticle, that will shut off supply to all recepticles for poster? Thanks


    My scanner isn't working either. Must be sunspot activity. What you are describing is an "EPO" circuit that is used in computer rooms. There are usually EPO pushbuttons at each exit which drop out all power to the room. Many industrial applications have "E-Stop's" at places where someone could get tangled up in machinery.

    This is basically a 3-wire motor start/stop circuit, with multiple stop buttons. Instead of a motor starter, you are pulling in a contactor to control the receptacles. (In a computer room, the circuit is usually connected to a UV trip on the main circuit breaker) Here is a link to a motor control page. Figure 3 shows the circuit. I couldn't find one with multiple stops, but you wire all the stop buttons in series. In an EPO circuit, the "Start" button is usually a key switch. All the switches are momentary contact.

    Please note this circuit will also drop out on power loss.


    http://http://ecmweb.com/training/electrical_basics/electric_ladder_logic_basics/

    Which beggers the question, why go through all this when a simple switch will drop out power to all the receptacles. I have a feeling this is not a residential application, and the OP should get a qualified contractor to install the circuit.
  • May 15, 2009, 02:43 PM
    Stratmando

    I was thinking of Single pole switch, with Push to open circuit, normally they would all be out in the closed condition.
    None would be momentary, all would be in series with power to the recepticles.

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