TV/Inverter Wiring Questions-gctid387453

[Guest]

So I just got an LED backlit TV/DVD player for the boat from Sam's club this last weekend for $200 (JVC LT-22DE72) (http://www.walmart.com/ip/JVC-22-Cla...142050&veh=cse) and got the 2 year extended warranty. I picked it based on the size, DVD load location, and low power consumption as well as the price. The only thing is it's an AC TV, but it only draws 35w. I'll be mounting it with something like this (http://www.google.com/products/catal...d=0CL8BEOUNMAE) with an 8x8 stainless backing plate on each side of the bathroom wall, which can also double as a mirror. So I'm figuring I'll have to wire some stuff up for this and I'm getting a 115 AH deep cycle battery which will run this and my extra bilge pumps.

THe questions I have are what I should chose for an inverter and how I should wire it up. I was thinking of just running some 12 gauge black and red wire up to the cabin where I would onnect it to a cigarette lighter style socket (http://www.google.com/products/catal...d=0CIQBEPMCMAA). Then when I want to use the TV, I can just plug in one of those cigarette lighter 75 or 100w inverters (http://www.abesofmaine.com/item.do?i...100W&l=FROOGLE) to run it, then unplug it so theres no draw when I'm not using it. And I figure the small inverter is better for efficiency and I'd never need to use anything other than the TV, cell phone charger, or maybe laptop (65w).

Just wanted to see what you guys thought of this plan for wiring like this, or if you had any other suggestions/cautions. I plan on just removing the battery after the weekend to charge it since I trailer the boat anyway as of now. Ad I'm also planning on using fine stranded 12 gauge wire, which is supposed to be good for 20 amps, and I'll fuse for 15.

Thanks, Mike.

[Guest]

My advice is to use a perfect sine wave inverter. More costly but you may damage your new TV with a square wave type. I learned that lesson the hard way. Modern LCD, LED TV's are pretty finicky about their power purity and the delicate computer based innards are not as tough as the old CRT types.

Also, even though the TV only draws 35w, you have the initial turn-on power surge to consider. The power surge can be as high as 6 times the current draw while in use. I'd recommend a 300w inverter minimum.

Any handy 12v source will do the trick, just be sure to match the wire gauge with the distance from the source. Longer distance, thicker gauge.

[Guest]

Do you have a specific brand you'd recommend for a pure sine wa ve inverter? I actually just sent JVC an email to see if it is ok to use modified sine wave or if it requires pure sine wave. I'm hoping to get an answer, companies usually tend to let my technical design questions slide because they don't want to find the answer. Thanks for the help though, I'll definitely go with a little bit larger inverter then.

[Don9]

9986mkoh wrote:
So I just got an LED backlit TV/DVD player for the boat from Sam's club this last weekend for $200 (JVC LT-22DE72) (http://www.walmart.com/ip/JVC-22-Cla...142050&veh=cse) and got the 2 year extended warranty. I picked it based on the size, DVD load location, and low power consumption as well as the price. The only thing is it's an AC TV, but it only draws 35w. I'll be mounting it with something like this (http://www.google.com/products/catal...d=0CL8BEOUNMAE) with an 8x8 stainless backing plate on each side of the bathroom wall, which can also double as a mirror. So I'm figuring I'll have to wire some stuff up for this and I'm getting a 115 AH deep cycle battery which will run this and my extra bilge pumps.

THe questions I have are what I should chose for an inverter and how I should wire it up. I was thinking of just running some 12 gauge black and red wire up to the cabin where I would onnect it to a cigarette lighter style socket (http://www.google.com/products/catal...d=0CIQBEPMCMAA). Then when I want to use the TV, I can just plug in one of those cigarette lighter 75 or 100w inverters (http://www.abesofmaine.com/item.do?i...100W&l=FROOGLE) to run it, then unplug it so theres no draw when I'm not using it. And I figure the small inverter is better for efficiency and I'd never need to use anything other than the TV, cell phone charger, or maybe laptop (65w).

Just wanted to see what you guys thought of this plan for wiring like this, or if you had any other suggestions/cautions. I plan on just removing the battery after the weekend to charge it since I trailer the boat anyway as of now. Ad I'm also planning on using fine stranded 12 gauge wire, which is supposed to be good for 20 amps, and I'll fuse for 15.

Thanks, Mike.

Did you look at any of the AC/DC HDTV's with internal DVD player?

[Guest]

We picked up a new Vizio 32" from Sam's last year when we got the boat. We run it on the dock power, genset, and our 3000 watt modified sine wave inverter for hours at a time. We use a clearwire internet setup for the Netflix and Hulu along with a satellite antenna setup.

We have had zero problems with the tv, direct tv receiver, or other electronics on the modified sine wave except for: the controller burned out on our electric blanket, a sears charger for battery powered drills burns out the protection fuses (easily replaced when I forget to unplug it when on the inverter), and some cellphone and laptop chargers fail. It won't take long for you to figure out which ones fail.

We solved the electric blanket problem by getting one of the newer low voltage controller types which by the way is wonderful in the Northwest.

I have installed surge protectors on some outlets and that seems to have solved the cellphone charger problem.

+1 on buying the full wave inverter...the prices aren't that much higher than the modified compared to a few years ago

[captharv]

Some basic inverter things.

this is the biggie. A 300 wat inverter @ 12V is drawing a maximum of 28 amps. (90% efficient), and may draw 4 amps or so in your case. However, as said, the draw could exceed 10 amps during turnon. Inverters have a low voltage cutoff to protect themself from low voltage. The voltage only has to be present for a few miliseconds for it to trip. (high spped integrated circuits). Reason:

(I will exagerate for clarity) 100 watts at 15 volts is about 6 amps. 100 watts at 10 volts is 10 amps. The components intrernally, may only be rated at, say, 8 amps by design (an 8 amp device is cheaper than a 10 amp one) So, they may set the tripout at 7 amps to protect themselves. Compounding the problem is the wire voltage loss at current. lets use .2 ohms. .2 O at 10 amps drops 2 volts. An inverter being supplies at 12.6 volts would have 10.6 at the inverter at that current. Most inverters trip out at about 11.9 (also to protect the batteries.).

Now, by use of larger diameter wire, the resistance is .02 amps, it will only drop .2 volts, and its happy....

So, without knowing the way you ar going to install the inverter, how far away, etc, I would try to keep it close to the battery(s), and use at least a #4 wire.

The wiring from the inverter is not as critical. 35 watts at 120 volts is a bit over 0.3 amps. You can use an extension cord between the TV and inverter.

My 600 watt inverter is 6' from the batteriy bank. I used 3/0 because a friend had a couple of spools of it, and I invisioned a larger inverter later on to run a microwave under way. My inverter does not trip out. (3/0 conductor is as large as mens fingers. this is $eriou$ wire.)

A rule of thumb with wire. Every three wire gauge sizes had twice the cross section (roughly) and can handle twice the current. generally, 14 is 15 amps, #12 is 20, 10 is 30A, 6 is about 70A, and #4 is used on car starters drwing 100-125 amps.

Copper costs few pennies (pun intended) but you get whet you pay for.

[Guest]

Hey I bought a 12v LED TV that has its own transformer at the plug that outputs 12V. Cut TV plug off wired direct to battery seems to be working fine. Am I missing something going to burn TV up?

[Guest]

Thanks for the suggestions!

And yes I had looked into a couple of the dual voltage TVs before, but I couldn't find one the size or DVD load location I wanted. Plus I didn't really feel like paying $300+ for a TV that didn't come with any kind of warranty, and I'd still have to do all the same work minus an inverter. But then I wouldn't have an AC plug available for anything else either.

And thanks too captharv, I've also been looking at how to set up the inverter as you mentioned. I know it's moreAn efficient to run the longest portion of wire after it has been converted to 120v as opposed to 12v. I was looking for a place to mount the inverter, but the only 2 options are in the engine compartment area near the battery or all the way up front right near the TV. That was part of the reason for the cigarette lighter socket approach if that was possible. Then I could just plug it in when I was going to use it, and only then. But I'll still put some thought into it before I decide how I'm going to set it up next week or this weekend. Open to any good suggestions I may not have thought of though.

And as far as the cutting of the wires to the TV an hooking it to the battery, I'm not so sure. If the transformer did indeed convert the 120 AC to 12 DC, then you should be ok. But you're still dealing with a range in voltage of the batteries a little outside of 12v.. I'm really no expert on the TVs and what they require though.

[Guest]

A regular cigarette lighter inverter is fine for the TV/DVD, it does not care in the least about the fact that those put out a VERY crappy square wave. Only things which rely on a waveform do, electric blankets (due to the controller) and AC motors (which actually use the waveform) are perfect examples of things which would care... though many combinations will still work fine.

I went with regular AC TVs and could not be happier, much lower cost and the selection was 20X what was available in just DC TVs. Would be different if we spent more than a night on the hook without running the engines, but we don't.

[Guest]

My only experience with all this is having to replace the 22" Phillips LED/DVD on the boat I bought last August. The PO had installed a 1000w square wave inverter and hooked the TV to that. The TV would turn on only intermittenly and turn itself off on a whim. The inverter was not the problem. Eventually the TV just died. It would no longer even power up even on line power.

While researching TV's on the internet I did some studying about inverters, particularly their usage with LED/LCD TV's. I learned that the newer TV's do not like dirty power one bit and anything less than pure sine wave will shorten their life. I forget which model inverter I chose but I didn't bother buying the marine version. That saved a good chunk of change right there. Mine lives in a cupboard in the galley, not in the engine room though so you may want to take that into consideration when you decide about placement.

[Guest]

telebob wrote:
While researching TV's on the internet I did some studying about inverters, particularly their usage with LED/LCD TV's. I learned that the newer TV's do not like dirty power one bit and anything less than pure sine wave will shorten their life. I forget which model inverter I chose but I didn't bother buying the marine version. That saved a good chunk of change right there. Mine lives in a cupboard in the galley, not in the engine room though so you may want to take that into consideration when you decide about placement.

Sounds like an old wive's tale... LED/LCD TVs really don't care what the power looks like in terms of the sine wave's "noise", though they may care more about RF interference.

The reason for this is these TVs operate off DC - to turn AC into DC, they have to rectify the AC waveform to first remove the negative portion of the waveform, and then they use capacitors to smooth the "wave" into one continuous DC voltage, which is then passed through a transformer to give somewhat near the needed output, and regulated to be almost the exact output. So, the guts of the TV never see any of the waveform - they just see pure DC, which is why a straight DC television is more efficient than going through both the inverting process of creating the waveform from DC (probably only 75% efficient on a small 100W inverter), then back to DC at almost the same voltage they started with

This is all much more reliable than taking a TV which expects a regulated 12v input using an external transformer, and connecting it directly to the 12v system on your boat as many people do, which is anywhere from ~10.8v to as high as ~15v in typical operation. TVs designed to connect directly to a 12V system will have an on-board regulator to handle varying input voltages.

[Guest]

I'm not an electrical engineer. All I know is what I've read on the subject and what has worked in my application. I have no idea how the rectifier stage is designed and how it handles square wave vs. pure wave current. If you can say with certainty that the rectifier stage in an LED/LCD TV doesn't care about the waveform it sees then your assertion is correct. If not, well...

I'll stick with the pure wave inverter, it works just fine and will work for any inverting applications.

[Guest]

I'll let everyone know what answers I get from the company. JVC forwarded it to another division, or so they said.

[Don9]

9986mkoh wrote:
Thanks for the suggestions!

And yes I had looked into a couple of the dual voltage TVs before, but I couldn't find one the size or DVD load location I wanted. Plus I didn't really feel like paying $300+ for a TV that didn't come with any kind of warranty, and I'd still have to do all the same work minus an inverter. But then I wouldn't have an AC plug available for anything else either.

And thanks too captharv, I've also been looking at how to set up the inverter as you mentioned. I know it's moreAn efficient to run the longest portion of wire after it has been converted to 120v as opposed to 12v. I was looking for a place to mount the inverter, but the only 2 options are in the engine compartment area near the battery or all the way up front right near the TV. That was part of the reason for the cigarette lighter socket approach if that was possible. Then I could just plug it in when I was going to use it, and only then. But I'll still put some thought into it before I decide how I'm going to set it up next week or this weekend. Open to any good suggestions I may not have thought of though.

And as far as the cutting of the wires to the TV an hooking it to the battery, I'm not so sure. If the transformer did indeed convert the 120 AC to 12 DC, then you should be ok. But you're still dealing with a range in voltage of the batteries a little outside of 12v.. I'm really no expert on the TVs and what they require though.

I only mention because I recently purchased a AC/DC HDTV on Amazon (no tax) that worked well for me and thought it could be an option for you or anyone else who reads your thread and also wanted to install a similar TV. I purchased the http://"http://www.amazon.com/gp/pro...s & DVD Player and very satisfied with the product. They also have the 22" for $219. I just plug it into the 12V cigarette lighter type outlet.

[Guest]

Oh, no I do appreciate the recommendation. I just found that this would probably better suit me for what I wanted, I guess we'll find out. I'm going to use a 140w (280w surge)Schumacher cigarette lighter receptacle modified sine wave inverter I got from walmart for $20. I talked to one of the technicians that works for JVC and he said that the AC electric supply is just filtered immediately and turned into DC to run the TV, so for all it matters it could be a square wave. He also said that the surge would be hardly anything, and is just charging up the capacitor. Plus the inverter has a surge factor built in.

So that's how I'm going to set it up. I have some 8g wire I'm going to run to cigarette lighter receptacle, fuse it back by the battery box, and let it run like that. I may grab an amp meter to watch it too.