12 volt tv or 110 volt tv?

[pokgunner]

We mostly boondock so keeping power consumption down is important. At first I thought switching to a 12 volt tv would be a no brainer. But then. Based on every spec I have read a 110 volt tv uses about half the power that a 12 volt tv uses. Is this true, or is it some kind of creativity in the specs?

Example; the 32" 12volt Television, by Jenson, specs says it uses 90 watts. For a 120volt 32 inch, by VIZO, its 32 watts, all features seem the same or very similar. I have found several 120volt 32” tvs that claim under 45 watts and no 12 volt tvs that claim under 65 watts.

Sticking with a 120 volt tv makes no intuitive since. The 12 volt tv needs only to covert to the dc voltage it was designed for. The other option has to covert 12 volts dc to 120 volts ac so that the TV can then covert to its design voltage DC. How could the latter be more efficient?

Perhaps Isaac-1, in a similar thread last year, is correct and the newer design for the 120 volt tvs are more efficient than the older design used for 12 volt tvs. But 50% more? More than enough to overcome the losses through the inverter?

I am suspecting that the DC tv specs provide some kind of peak loading for wattage and the AC tv specs provides some kind of average loading for wattage.

So which would allow me to boondock longer and run the generator less, 12 volt tv or 120 volt tv?

[Camper25]

I just bought a new LG tv that had a 120v to 19v dc power brick, so I bought a 12v to 19v converter to power it in my trailer.

https://www.amazon.com/Converter-5A-...18&sr=8-2&th=1

[GypsyR]

I had to do a circuit board swap in our 55" 4K house TV. I found it interesting that the actual internal voltage it uses are 12 volts and 5 volts DC. Not my area but my first thought was that one could pretty easily eliminate the AC conversion and just run the TV on straight DC. I also wondered how many other flat screens are DC internally.

[Archer2]

Originally Posted by GypsyR

I also wondered how many other flat screens are DC internally.

The answer is “all of them”.

[computerguy]

My Sony had a brick to convert from 120v to 19.5.
I bought a transformer thingie and run it off of my 12v no problems. It steps it up from 12 to 19.5.
I never did a side by side comparison to see how many watts the different type consumed.

[Newps]

Originally Posted by pokgunner

Example; the 32" 12volt Television, by Jenson, specs says it uses 90 watts.

90 watts at 12 volts.

Originally Posted by pokgunner

For a 120volt 32 inch, by VIZO, its 32 watts,

32 watts at 120 volts.

[PbdBlue]

1st watts are watts regardless of voltage. Obviously if the voltage is different the amperage will also be accordingly. That said AFIK there are no 32" or larger tv's that use an external power brick. Maybe I'm wrong on that but I haven't ever found one. Really if you want something in that size range your only option is an inverter. Recommend getting a small PSW inverter (like 100W) as it will be much more efficient than a large one.

[pokgunner]

Thanks PbdBlue, watts is watts, what I cannot figure out is why are the specs for a DC TV about TWICE the wattage as a similar AC TV? Particularly since an AC TV has to convert back to DC.

The difference in wattage is so great it makes the losses of an inverter to power an AC TV inconsequential.

It makes no since unless the various specifications are not apples to apples, or the DC TV uses old circuitry that has much more losses than the new AC TVs. (a way for manufactures to clear out left over circuit boards?)

[computerguy]

Originally Posted by PbdBlue

...That said AFIK there are no 32" or larger tv's that use an external power brick. Maybe I'm wrong on that but I haven't ever found one...

Yep, you just haven't found them. They are out there. My 2 Sonys use bricks. Model numbers KDL40W600B and KDL32R420B. One 40" and one 32".
As I said earlier in the thread I swapped the brick for a step up transformer to run them on 12v and not need an inverter for them.

[DavidEM]

I have done a little experimenting with direct DC powered TVs, TVs that use a brick to convert AC to 18-20V DC and direct AC powered TVs. Well there are no true AC powered TVs as sooner or later it all gets converted to DC to power the internal TV electronics.

I found that using a small, 150W inverter to power either the brick type or direct AC powered TVs didn't matter much in terms of total wattage, maybe a 15% difference which is probably inverter losses. I also tried using a DC to DC converter to take the coach's 12V DC and boost it to the 18-20V DC that the TV needed internally. That also had about the same 15% losses as the inverter.

So, buy the best TV that works for you and then set up a small inverter or DC to DC converter to power it. You won't find too many 12V DC powered TVs as they are all 18-20V today.

David

[Ray,IN]

Originally Posted by PbdBlue

1st watts are watts regardless of voltage. Obviously if the voltage is different the amperage will also be accordingly. That said AFIK there are no 32" or larger tv's that use an external power brick. Maybe I'm wrong on that but I haven't ever found one. Really if you want something in that size range your only option is an inverter. Recommend getting a small PSW inverter (like 100W) as it will be much more efficient than a large one.

I suspect the difference in their thinking is the conversion factor from 12VDC to 120VAC amperage and vica-versa.

[PbdBlue]

Originally Posted by computerguy

Yep, you just haven't found them. They are out there. My 2 Sonys use bricks. Model numbers KDL40W600B and KDL32R420B. One 40" and one 32".
As I said earlier in the thread I swapped the brick for a step up transformer to run them on 12v and not need an inverter for them.

Great to know but I think both of those have been discontinued. I have a smaller Samsung in the MH bedroom that I did the same thing with. I just hadn't found a big tv.

[PbdBlue]

Originally Posted by Ray,IN

I suspect the difference in their thinking is the conversion factor from 12VDC to 120VAC amperage and vica-versa.

'
Probably more to do with the backlighting which is the biggest drain in most led tv's. I suspect the Jensen uses older more energy hungry tech.

[TR4]

Originally Posted by computerguy

Yep, you just haven't found them. They are out there. My 2 Sonys use bricks. Model numbers KDL40W600B and KDL32R420B. One 40" and one 32".
As I said earlier in the thread I swapped the brick for a step up transformer to run them on 12v and not need an inverter for them.

My Sony XBR 49” uses a power brick as well.

Bill