What size inverter ?

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sc4668

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Apr 18, 2017
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Brooklyn, MI
Will be going to Quartzsite next month and will be boondocking. I would like to have an inverter to run my TV and DVD player. The TV is a 32 inch Vizio  and the DVD is a Panasonic. I can not find the current draw specs on these but similar units look like they draw about 200 watts total. I am looking at a 300 watt pure sine wave inverter that will plug into the 12V lighter plug behind the TV. Do you think this will be a big enough inverter?
 

PJ Stough

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Central Iowa
Probably, yes.  We used to run our TV and charge our phones and computers on a 300 watt modified sign wave inverter. It was the stock inverter in our Winnebago.
 

ChasA

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Mar 21, 2009
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I don't think you'll get 300 watts from a cigarette lighter plug. I think you'll have to hardwire from a good 12v source. 200 watts will draw approximately 20 amps. Those lighter plugs are only good for 10 to 15 amps. Those small inverters do come with a lighter plug. But the instructions will tell you that you can only get 100 to 125 watts. And to get the full rated wattage,  you have to use a larger wire and fuse.
 

Larry N.

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Westminster, Colorado
sc4668 said:
Correct me if I am wrong but 300 watts is less than 3 amps.
Watts = volts X amps, so amps = watts/volts so:

300/120V = 2.5 amps
300/12V = 25 amps, not counting internal losses in the inverter.

You must be careful which units you're using for the calculation.
 

Isaac-1

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SW Louisiana
I would suggest staying with a reputable brand, some of those output watt ratings on the cheaper import inverters is pure fantasy, perhaps something like https://smile.amazon.com/Victron-Power-Inverter-Phoenix-350VA/dp/B01EW5ZA94/
 

johnaye

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Aug 6, 2016
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Arch Hoagland said:
Buy one of these and you'll know exactly how much current you will be drawing.

https://www.walmart.com/ip/P3-Internatoinal-P4400-Kill-A-Watt-Energy-Monitor/14282370?wmlspartner=wlpa&selectedSellerId=1330&adid=22222222227000427963&wl0=&wl1=g&wl2=c&wl3=40330360712&wl4=aud-566049426865:pla-46054568209&wl5=9031807&wl6=&wl7=&wl8=&wl9=pla&wl10=100362769&wl11=online&wl12=14282370&wl13=&veh=sem&gclid=EAIaIQobChMI8sC-77Cv3wIVAr3sCh03WQHsEAQYAiABEgJMtvD_BwE
Just ordered one.  Thanks for the advice
 

AStravelers

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Nov 14, 2016
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San Antonio, TX
sc4668 said:
Will be going to Quartzsite next month and will be boondocking. I would like to have an inverter to run my TV and DVD player. The TV is a 32 inch Vizio  and the DVD is a Panasonic. I can not find the current draw specs on these but similar units look like they draw about 200 watts total. I am looking at a 300 watt pure sine wave inverter that will plug into the 12V lighter plug behind the TV. Do you think this will be a big enough inverter?
My flat screen 32" Samsung LED TV pulled less than 30 watts (about 2 to 2.5amps at 12V).  A DVD player should pull less than 10-15 watts.  Probably 5 watts. 
 

garyb1st

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Southern California
For your needs, a 300 watt inverter will probably work.  But as others have said, pulling that much from a 12 v plug is not the best idea.  Ideally you should hard wire it to your battery and if you decide to do that, consider going with a larger inverter.  Not much more money and allows you to run more stuff without having to buy a larger inverter later. 
 

Foto-n-T

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Jan 1, 2012
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Cody, Wyoming - Sometimes
I went from a 1,000 watt modified sine wave inverter to a 300 watt pure sine wave one when the 1k finally died.  300 watts is more than enough to power your entertainment system as that's what mine is used for.  My 1,000 watt inverter had an output meter on it and I found that the TV, amp and satellite receiver combined drew less than 200 watts.  I switched to a pure sine wave simply because I horse traded a buddy for it otherwise I'd have gone back to the modified wave unit.
 
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