calculating power consumption of a tv

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sqlpro

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#74705 5-Jan-2011 21:10

Hi guys
am just wondering if you've any ideas how to calculate power consumed by tv. interestingly manual does not say anything. on the back of this tv i see volts (240) and amps 1.7

its LG LED tv (47LE7500) ,i searched internet but to no avail. i contacted LG support too but they dont have a clue! they say it all depends environment/usage etc.,
i dont need exact numbers but an average (150watts for e.g.),

Thanks for the advise.

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#424418 5-Jan-2011 21:23

If it's 240V and 1.7A then the power used would be 408W (Power = volts x amps). I would guess that would be at full backlight etc but it's a worst case.

Dunnersfella

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#424419 5-Jan-2011 21:24

It's a little tricky to do...
And the importers comments re: usage patterns will influence things too. For instance, on an LCD or LED, having the motion smoothing features turned on / up will require more juice to be used... but no where near as much as cranking up the brightness though.
Are you looking for a specific reason? Or just out of curiosity?

sqlpro

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#424421 5-Jan-2011 21:33

i was curious why LG carefully eliminated power consumption from manual!

as all brands market LED being most power saving technology . i wanted compare with my previous tv (sony 50inch projection lcd with consumption 200 watts).

now am surprised with handle9 calculations, 408watts!! twice the amount my old tv!!!

dontpanic42

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#424423 5-Jan-2011 21:42

If you want a reasonably accurate reading, get one of these:

http://www.mitre10mega.co.nz/shop/electrical_hardware/electrical_outlets_fittings/elto_power_meter_103559/

Plug it into the power socket, and then plug the TV into it. Bingo, instant power usage data.

jjnz1

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#424433 5-Jan-2011 22:13

Handle9: If it's 240V and 1.7A then the power used would be 408W (Power = volts x amps). I would guess that would be at full backlight etc but it's a worst case.

That would be its rated value not actual.

The LG web site states power consumption @ 170 watts, and standby @ 1 watt.

As others have mentioned, that number would be lower depending on the settings/configuration used.

jjnz1

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#424434 5-Jan-2011 22:14

Sorry, heres the link.

http://www.lg.com/hk/tv-audio-video/television/LG-led-lcd-tv-47LE7500.jsp

sqlpro

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#424518 6-Jan-2011 06:53

jjnz1: Sorry, heres the link.

http://www.lg.com/hk/tv-audio-video/television/LG-led-lcd-tv-47LE7500.jsp

Thank you jjnz1. i did not find it before. but i accidentally found it on our energywise website. it says 99 watts ,different value from your link!!!
http://www.energywise.govt.nz/node/16708

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sbiddle

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#424527 6-Jan-2011 07:51

sqlpro:
jjnz1: Sorry, heres the link.

http://www.lg.com/hk/tv-audio-video/television/LG-led-lcd-tv-47LE7500.jsp

Thank you jjnz1. i did not find it before. but i accidentally found it on our energywise website. it says 99 watts ,different value from your link!!!
http://www.energywise.govt.nz/node/16708

Remember Hong Kong is 220V vs 230V in NZ so you won't get identical results.

As others have pointed out there are so many variables depending on tthings such as brightness and backlight settings that actual figures will be hard to come by.

stuzzo

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#424531 6-Jan-2011 08:25

Often the power figure quoted by manufacturers is simply the capacity of the power supply. As mentioned, modern TVs' power consumption varies greatly depending on settings, in particular backlighting. I find "Cinema modes" are generally some of the lowest power modes and closest to a correct calibration out of the store.

You can often half the power consumption of your TV just by changing the mode setting away from the bright showroom default.

A cheap "Wattmeter" will help you and be revealing for power consumption all around the house.

Cnet did a good series of articles on TV power consumption recently for further reading:

http://reviews.cnet.com/green-tech/tv-consumption-chart/

http://reviews.cnet.com/green-tech/tv-power-efficiency/

gzt

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#424638 6-Jan-2011 14:09

The numbers on the government website will be from the data supplied by LG (as a lab report) to the Energy Star qualification program.

LG were severely busted in the states a few years ago for tweaking their test setups to provide the results they needed. A few years before that LG paid compensation to consumers in Australia for inaccurate air conditioning energy star ratings. Most recently, in March 2010 LG were again busted in Australia for going as far as actually including a specific device in refrigerators to detect test lab temperature conditions and reduce the refrigeration to lower energy use temporarily and get the desired consumption result. Unbelievable.

This is all in the past of course ; ) back to the topic.

The Energy Star program has a set of requirements for test measurement, and I'm thinking if you want to test that specification you will need something a little better than a cheap meter. But hey, there might be a partial refund in it : )

Interested to hear what the cheap meters report tho. What's your geo? If you are close by I or someone else may be able to lend you one.

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sqlpro

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#424641 6-Jan-2011 14:19

gzt: The numbers on the government website will be from the data supplied by LG (as a lab report) to the Energy Star qualification program.

LG were severely busted in the states a few years ago for tweaking their test setups to provide the results they needed. A few years before that LG paid compensation to consumers in Australia for inaccurate air conditioning energy star ratings. Most recently, in March 2010 LG were again busted in Australia for going as far as actually including a specific device in refrigerators to detect test lab temperature conditions and reduce the refrigeration to lower energy use temporarily and get the desired consumption result. Unbelievable.

This is all in the past of course ; ) back to the topic.

The Energy Star program has a set of requirements for test measurement, and I'm thinking if you want to test that specification you will need something a little better than a cheap meter. But hey, there might be a partial refund in it : )

Interested to hear what the cheap meters report tho. What's your geo? If you are close by I or someone else may be able to lend you one.

thats scary ! i never thought even bigger brands would do something like that . if they are caught compensation will be huge compared to unknown brands. anyway thanks for the headsup gzt.
BTW my model seems to be from june 2010 .

am located in hamilton.

Ragnor

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#424651 6-Jan-2011 14:38

dontpanic42: If you want a reasonably accurate reading, get one of these:

http://www.mitre10mega.co.nz/shop/electrical_hardware/electrical_outlets_fittings/elto_power_meter_103559/

Plug it into the power socket, and then plug the TV into it. Bingo, instant power usage data.

+1 this

gzt

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#424662 6-Jan-2011 14:56

I'm in waitakere, ak. Can't help you there.

Energy Star did tighten up the program a bit this year and did do bit of random auditing (revoked energy star status for 25 CFL brands which did not meet use life requirements) but it is essentially and always will be a voluntary and honesty based reporting system. The states being the states, there is a law firm specializing in Energy Star actions.

My impression is Energy Star overall works quite well and LG were particularly stupid to risk their brand by trying to fake it.

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Dunnersfella

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#424765 6-Jan-2011 19:45

Interestingly, you never see Panasonic in NZ taking part in the Energy Star ratings system...
I think, personally, buying a TV based on Energy Star ratings is a little odd.
It's a very rough guide at best.

clevedon

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#424917 7-Jan-2011 10:22

Dunnersfella: Interestingly, you never see Panasonic in NZ taking part in the Energy Star ratings system...
I think, personally, buying a TV based on Energy Star ratings is a little odd.
It's a very rough guide at best.

Yep, it's the last thing I look at when buying something and the first sticker I peel off when I get it home.

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