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Generator help

  1. Nov 3, 2012 #1
    I live in the USA and was thinking about getting an Electric Generator just for my Livng Room.

    So it could power my T.V. my DVD Player and my Lamp.

    Now I know they have Electric Generators that have Battery Power some are Hand Cranked.

    I just need to know some things first about how they work?

    I know the Home Outlet has 120 Volts at 15 AMPs so 120 x 15 = 1,800 WATTs.

    So my Living Room Outlet is giving 1,800 WATTs of Power and I know just because my T.V. is pluged into the Outlet it is not useing the whole 15 AMPs.

    So if I got an Electric Generator and it gives 10 AMPs at 120 Volts would it not Power the T.V. because the T.V. is not useing 15 AMPs?

    Or how does this whpole thing work?
  2. jcsd
  3. Nov 3, 2012 #2
    Why do you want to generate power just to your sitting room? If you want to be covered for short term power cuts you might be able to fit UPSs where needed if you are talking about longer outages you need something with it's own engine.
  4. Nov 3, 2012 #3
    I am Sorry this is what I ment.

    If the Power goes out the only things I need to be powered is the Living Room
    The Lamp The T.V.
    The DVD Player

    I know what UPs are you plug your Device into it and plug the UPs into the Outlet.
    And the Outlet passes the power to the Device and at the same time it charges a Battery in the UPs.

    So if you loss power the Device pluged into the UPs starts runing off the UPs Battery I get this.
    But they do not last long and rundown.

    I do not want to get a Gass powered on because I do not want to fill it and keep the Gass and it only has to power my Living Room.

    So I thought they have maybe Hand Crank ones that you turn it by Hand for say 10 min. and they last for an Hour>
  5. Nov 3, 2012 #4
  6. Nov 3, 2012 #5
    Well I did read this on how to make a Genarator.

    Take a Motor with the Shaft sticking out and connect it to a Battery with the same Voltage as the Motor.

    When you turn the Motors Shaft I know how this is working you are spining the Magnet inside the Coil of Wire and the Motor is making powor I get this.

    So you are charging the Battery.
    But not all Battories can be charged and you can only run something that uses what the Battory can supply.

  7. Nov 6, 2012 #6
    I think what you are looking for is ether a UPS, or a battery with a inverter.
    Part of my hurricane kit is a 1000 watt inverter and 2 deep cycle batteries.
    http://www.harborfreight.com/1000-watt-continuous-2000-watt-peak-power-inverter-97047.html [Broken]
    The idea being that I can recharge the battery from the car.
    Inverters are good for tv, fan, and some lights, most will not start even a small
    Last edited by a moderator: May 6, 2017
  8. Nov 6, 2012 #7
    Well I read that you can Hockup a 9 Volt Car Battery to a 9 Volt Motter and when you turn the Motter Shaft the Magnet spins in the Coil to make Electric I get all of this.
    And this will recharge the Battery.
    And the Invert makes DC into AC but one thing.

    The Living Room Outlets give 120 Volts not 9 Volts so how can I Hock the Battery up to say my TV or DVD Player?
  9. Nov 6, 2012 #8
    The car battery is 12 volts DC, the Inverter has a 12 volt DC input, and a 120 volt AC output.
    The inverter has normal 110v outlets on it.
    Just plug you devices directly into the inverter.
  10. Nov 6, 2012 #9
    Ok thanks for getting back to me but on thing is the 12 Car Battery 15 AMPs?
  11. Nov 6, 2012 #10
    You actually want a deep cycle battery. something like this.
    http://www.atbatt.com/product/24022.asp?utm_source=frog&utm_medium=cpc&utm_content=textlink-automotive-batteries&utm_campaign=frog1&utm_term=SRM-24&gclid=COnNtKaeu7MCFcKPPAodaF0AhA [Broken]
    84 amp hours.
    84 amps times 12 volts is 1008 watts,
    So you could run 1000 watts for about 1 hour, or 250 watts for about 4 hours.
    They also make better deep cycle batteries, they just cost more.
    Last edited by a moderator: May 6, 2017
  12. Nov 6, 2012 #11
    Now I know ONE Amp is ONE big number of Electrons that will go past one point in one SEC.

    And my Living Room Outlet gives 15 AMPs so this is 15 Coulombs of Electrons that will go past One point in One SEC.

    But what I do not understand is Batteries are Rated as AMP Hours so when you say a 12 Volt Battery is 48 AMP Hours do you meen this.
    The Battery will last for 48 Hours but how many AMPs does it supply?
  13. Nov 7, 2012 #12


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    Gold Member

    48 amps for one hour or 1 amp for 48 hours.

    LCD TV uses about 150 W or 1.25 amps.
    Lamp, 60W or 0.5 amps.
    DVD player 15W or 0.125 amps.

    Total - about 2 amps.

    Inverters are not very efficient but you should get 24 hours using one and a 84 A/h battery.
  14. Nov 7, 2012 #13
    OK just one thing.

    You tell me a 48 Amp Hour Battery will give 48 Amps for 1 Hour I get this.
    But then you say it can also give 1 Amp for 48 Hour.

    If it can give 48 Amp for 1 Hour how can it also give 1 Amp for 48 Hour how do you bring the Amp down to 1 Amp?

    Or am I missing something?
  15. Nov 7, 2012 #14


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    Gold Member


    Volts is constant, so current depends on resistance. As resistance increases, amps decrease. So, by selecting a low resistance (e.g starter motor) I pull a lot of amps. By selecting a high resistance (parking lights) I only pull 1 or 2.

    W=VxA Re-arranged, V=W/A

    Again, volts is constant. So current depends on watts too. In this case, as watts increase so do amps. A 3 kW washing machine pulls more amps than a 60 W light bulb.
  16. Nov 7, 2012 #15
    Thank you I now understand how they will work.

    Now If I get a 12 Volt 48 Amp Hour Car Battery you tell me I should get a Deep Cycle Battery.
    What is a Deep Cycle Battery?
  17. Nov 7, 2012 #16
    A Deep Cycle Battery is
  18. Nov 7, 2012 #17
    Ok tell me if I have everything down Right?

    If I have a Deep Cycle 12 Volt 48 AMP Hour Car Battery it can be Drand and Re Chared over and over and last longer?

    If I take a Deep Cycle 12 Volt 48 AMP Hour Car Battery and connect it to an Inverter the Output will be 120 VAC and give 48 AMP for 1 Hour? And with 48 AMPs for 1 Hour I can run my TV and DVD Player and Lamp in the Living Room?
  19. Nov 8, 2012 #18
    biferi – where do you live? Is it cold there? Here where I am it is cold, so the main reasons to have a generator for power outages are to keep the furnace running (controls and circulating pump or fan) and to run the refrigerator (so the meat doesn’t spoil). Compared to these, a DVD player and a TV are small loads. So, just keep your priorities in the right order! Also, if you have a long power outage, there is no sense in watching TV because they will just say over and over, “the power is still out and it is cold.” You knew that already! If you want to watch DVDs maybe get a portable player and some batteries for it, that will be cheaper than the big battery and inverter discussed above.
  20. Nov 8, 2012 #19
    Soory I live in the USA but this is more of a Fun Project for me.
    You see we Lose Power even if it Rains a little.

    So I just thought it would be nice to have a GEN for watching T.V. and to plug the Lamp in.

    So when you Buy an Inverter it will Output 120 VAC but what will the AMPs be?

    What I mean is if I have a 12 Volt 48 Amp Hour Batter the Inverter will output 120 Volts but will it just pass the Current through as is?

    So I still will get 48 Amp for 1 Hour?
  21. Nov 8, 2012 #20
    Most auto parts stores and walmart will have deep cycle batteries.
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