battery question

[musherdeb]

i have the battery set up and i am happy to have my frig back. no elec. on property yet. i am wondering how many batteries i have to use to be able to watch tv. i can turn the generator on bur had read a lot of folks can watch tv on the battery. i am lookinginto solar as well.

[JiminDenver]

We have no idea if the OP even has a TV. lol

If you want to go low power, I have a 7 inch rechargeable LED flat screen TV that can be charged in the truck in between uses. It could be plugged into the trailers 12v and run all day and still not use a lot of power. We don't get reception so usually we use a nine inch portable rechargeable DVD player instead.

Last trip we took a 15 inch TV/DVD combo that I replaced the brick with a 12v cord. It's rated at 65w.

We do have a 19 inch flat screen rated at 65w but it's 120v only. Will be nice and easy to run on a small inverter if we ever have reception.

A lot depends on how much power the TV uses, how long it will be running and how close are you to draining your current battery in between charges. Last year we use a generator for two hours a day to charge our single grp 27 battery with 95ah when fully charged. We do use the furnace at night but also use LEDs and had no problem running the smaller TV or DVD player a few hours a day.

You mention solar.
Solar may work well for you IF you park in the sun or can put a portable set up in the sun AND can make your battery last a day or two between charges. (some days are not so sunny)
We started using a 230w portable set up this year and not only does it keep the battery much closer to full than the daily 2 hr runs did, it can run the TV during the day without the battery ever losing a volt. Actually it'll run the lights, furnace, fans and the battery will stay in float. The only time the battery is not in float or above is after sunset and before charging starts at 6am. the discharge on our larger battery is even less over night.

Last thing is if you are going to need a dish and receiver or there is a amplifier on you antenna, make sure you consider the power usage there too.

[westend]

pianotuna wrote:
Hi Westend,

Yup, tv's have gotten way more efficient. I don't use one.

Yup, and glad you don't have one, that allows more "Don-posting-time". That is something that's good for me, I'm fer it!

[TucsonJim]

pianotuna wrote:
Hi Jim,

You have not allowed for inverter losses which are at least 12% nor voltage drop losses on the DC side. You have not allowed for power factor losses, either. 140 watts of television will draw about 14 amps from the battery bank. If you want, go check it with a fluke clamp on meter.

It is almost always a mistake to "low ball" battery drains.

TucsonJim wrote:

pianotuna wrote:
Hi,

A 140 watt TV will draw about 14 amps from the battery bank.

14 amps is a little high. Current can be derived as follows: Wattage/Voltage = Current. So 140 Watts/12 Volts = 11 2/3 Amps.

Good points. Didn't realize you were talking about using an AC TV through an inverter.

[pianotuna]

Hi Westend,

Yup, tv's have gotten way more efficient. I don't use one.

[pianotuna]

Hi Jim,

You have not allowed for inverter losses which are at least 12% nor voltage drop losses on the DC side. You have not allowed for power factor losses, either. 140 watts of television will draw about 14 amps from the battery bank. If you want, go check it with a fluke clamp on meter.

It is almost always a mistake to "low ball" battery drains.

TucsonJim wrote:

pianotuna wrote:
Hi,

A 140 watt TV will draw about 14 amps from the battery bank.

14 amps is a little high. Current can be derived as follows: Wattage/Voltage = Current. So 140 Watts/12 Volts = 11 2/3 Amps.

[westend]

TucsonJim wrote:

pianotuna wrote:
Hi,

A 140 watt TV will draw about 14 amps from the battery bank.

14 amps is a little high. Current can be derived as follows: Wattage/Voltage = Current. So 140 Watts/12 Volts = 11 2/3 Amps.

Not only that but my newer Magnavox 32" LED/LCD screen operates at 32 watts. Allowing for a 10% loss through inversion, draw would be in the range of 3 amps at 12VDC. If just using a single battery, the OP would be able to get a few hours of use daily and a small solar system would make up the difference easily.

[TucsonJim]

pianotuna wrote:
Hi,

A 140 watt TV will draw about 14 amps from the battery bank.

14 amps is a little high. Current can be derived as follows: Wattage/Voltage = Current. So 140 Watts/12 Volts = 11 2/3 Amps.

[pianotuna]

Hi,

A 140 watt TV will draw about 14 amps from the battery bank.

[TucsonJim]

If you'd like to watch TV using your battery, you need one of the following:

1. A TV that is designed for 12 Volts. It will have a "cigarette lighter" plug.

-or-

2. An inverter which converts 12 Volts Direct Current (Battery Power) to 120 Volts Alternating Current (Wall voltage).

If you want to go the inverter route, you'll need to get one with enough wattage capability to run your selected TV. For example, if your TV operates at 140 Watts, you'll probably need an inverter with a minimum of around 200 Watts.

Needless to say, either the 12V hookup, or the 120V hookup with an inverter will drain the battery, so you'll need a method to keep it charged.