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-   -   Intermatic wall timer/switch (https://www.askmehelpdesk.com/showthread.php?t=126249)

  • Sep 5, 2007, 03:09 PM
    BAnderson
    Intermatic wall timer/switch
    I would like to install one of those cool in wall programmable timer/switch but have a question. The switch I would like to replace controls 2-500watt halogen lights, 2-150watt incandescent flood bulbs, 60watt outside door light, and finally 2-150watt halogen lights which totals up to 1660watts.

    With that said I need a timer/switch that can obviously handle 1800 max watts, so Im looking at this Intermatic timer here: Intermatic Timers - Consumer Indoor Timers - In-Wall Timers - SS7C

    What is confusing the hell out of me is that it doesn't list the max watts but instead this:

    Resistive Heater 15 Amp 120-277 VAC
    Tungsten Incandescent 15 Amp 120 VAC
    6 Amp 208-277 VAC
    Ballast Fluorescent 8 Amp 120 VAC
    4 Amp 208-277 VAC
    Motors 1HP 120 VAC
    2 HP 240 VAC
    DC Loads 4 Amp 12 VDC
    2 Amp 28 VDC

    So with this info Im taking this as this will handle a full 15amps based on the Tungsten Incandescent 15 Amp 120 VAC rating but Im not sure and really don't want to waste $50-$70 on this timer if it will not work.

    Any info will be GREATLY appreciated as well as maybe other suggestions although I would really like to stick with one of these cool in wall timer/switches :D
  • Sep 5, 2007, 04:22 PM
    KISS
    Power(W) = voltage(V) * amps(I)
    1800 watts =120 * 15

    So, your at the max. OK
  • Sep 5, 2007, 05:31 PM
    BAnderson
    Quote:

    Originally Posted by KeepItSimpleStupid
    Power(W) = voltage(V) * amps(I)
    1800 watts =120 * 15

    So, your at the max. OK


    Not sure if I follow you? I understand the whole 15amp circuit=1800 watts what Im needing to know is if this particular intermatic wall timer/switch that I listed above will be able to handle a load of 1800 watts max?:confused:


    Tungsten Incandescent 15 Amp 120 VAC<--------This is what is confusing me, does this mean what your saying? If I am reading this right its saying 15 amp 120 VAC which as you stated would be 120*15 to give 1800 watts. I guess I just need someone to let me know if Im reading this right?

    Thanks
  • Sep 5, 2007, 07:24 PM
    KISS
    Normal light bulbs are tungsten.
    Halogen lamps are actually tungsten-halogen.
    So you use the tungsten rating of 15 AMPS

    The 15 amp rating * the voltage = 1800W
    re-iterating: Timer will handle 1800W tungsten

    1660<1800 so your within the rating of the timer.

    If P=VI then I=P/V; Your circuit will draw 1660/120 or 13.8 amps

    which is only an 8.4% safety factor assuming a 15 AMP breaker in the fuse box.

    Variations an manufacturing and the lamps and line voltage COULD cause nucense trips, but if you are already using these, then a 15A circuit will be OK.

    Ratings are not an exact science. It won't die at 1801 watts.

    Aside: Tungsten filaments typically draw about 10x their current for a short time at startup.

    Better?
  • Sep 6, 2007, 01:01 PM
    BAnderson
    Quote:

    Originally Posted by KeepItSimpleStupid
    Normal light bulbs are tungsten.
    Halogen lamps are actually tungsten-halogen.
    So you use the tungsten rating of 15 AMPS

    The 15 amp rating * the voltage = 1800W
    re-iterating: Timer will handle 1800W tungsten

    1660<1800 so your within the rating of the timer.

    If P=VI then I=P/V; Your circuit will draw 1660/120 or 13.8 amps

    which is only an 8.4% safety factor assuming a 15 AMP breaker in the fuse box.

    Variations an manufacturing and the lamps and line voltage COULD cause nucense trips, but if you are already using these, then a 15A circuit will be OK.

    Ratings are not an exact science. It won't die at 1801 watts.

    Aside: Tungsten filaments typically draw about 10x their current for a short time at startup.

    Better?


    :D Thanks for the help. After I saw the web site and saw this: Tungsten Incandescent 15 Amp 120 VAC--I was pretty sure it would handle 1800watts but when I called one of the local supply shops to see if they had it in stock I also asked how many watts it could handle and he said 500 but he may have looked at the other model, but ever since then I was just uncertain and since it never came right out and said xxx watts I just wanted to cover my rear before I cause something to happen that could have been prevented. Thanks so much for the info I can relax now :)

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