TV/DVD 12v Vs Shore Power

Now that we are on our fourth camper battery, it is worth passing on our experience in regard to the television being powered off of the battery. Our only use of the television is when cold and/or wet weather forces us to be in the cabin for prolonged periods. That is typically in the winter: daylight doesn't last as long, and extended periods of ran are unavoidable just about everywhere. So this post will have no relevance to most of you who don't camp in such conditions or take extended trips in your camper.

During the summer, our electrical needs are mostly met with our 100 watt solar panel. At noon in Las Vegas in April it will put out about 4 amps or so. But in Florida in mid-December it may only pump out 1 amp at noon (our panel is mounted horizontally, and we were near a large urban area, so there was plenty of pollution to filter out some of the sun). It has taken us a while to figure that out, and is a big part of our concern about running the television directly off of the battery.

This spring, our one-year-old battery was starting to show signs of its impending demise. So we switched to running our generator for a few hours per day to keep the battery topped off (I don't care how quiet generators have become, they still are obnoxious when you are sitting six feet away - but it is tolerable when watching television). Whenever we run the generator, we plug our Dometic into it directly, to avoid the battery being drawn down as fast as it is being charged by the camper's onboard charger (the generator is plugged into the shore power inlet to power the charger). Until recently, we had no way of removing the television's load on the battery.

If my famously faulty memory is correct, when the Dometic is cycling it draws something like 6 amps. The television is the next major load, drawing about 3 amps (according to the guy at our hitch shop ,who wired our solar panel).

So we had a failing battery, the Dometic running directly off the generator and we were watching a DVD on the television for a couple hours with virtually no other load on the battery. The net effect after the DVD was over? Virtually no increase in the battery's charge. We had just run the generator for two+ hours, and we weren't much better off than when we started.

That got me thinking, don't most televisions ship with a transformer/power supply to convert 110v to 12v? Yes, they do. But our campers aren't built to utilize that, they are wired directly to the battery. So we decided to get a transformer/power supply in order to avoid putting this unnecessary load on the battery, and thought we would pass this along in case it is of interest to any other owners.

Our television is a Supersonic SC-1512 (again relying upon my famously faulty memory), so we obtained a power supply for it, plugged same into the empty air conditioner 110v duplex outlet, and routed the power cord to the television. On the television, we unplugged the existing 12v power cord, opting to leave it in place (just in case a future owner - probably a niece or nephew, once we both drop dead - wants that option). We then plugged in the new power supply cord, secured the wiring with zip ties, and we were in business. The whole project took less than 10 minutes.

We now can only watch television on shore power or generator power. So we don't risk hastening the demise of a failing battery (or a brand new one, for that matter).

Speaking of batteries, most Group 24 deep cycle batteries will work in our campers (at least in those with the AGM battery option), though some Group 24 batteries have dimensions that can make it a difficult fit in the battery compartment (there are some minor adjustments that can be made in the battery compartment, though the dimensions quoted on some batteries make me believe that some probably won't fit). As such, it can be a chore to get a replacement battery. And the batteries sold at local battery stores are often twice what they cost vs when ordered over the internet ($350 vs. $175).

This picture shows new power supply, existing 110v duplex outlet, and an existing USB extension cord that is routed along the bottom of the television to the cabinet on the far side of the television:


The plug for the existing factory 12v wiring:


The new wiring from the 110v power supply (the old wiring is still in place behind this):


Securing the wiring in place:


Securing the wiring in the cabinet:


Everything trimmed up and working:

 

Great thread! I don't have a TV but found the information helpful.

 

Thanks for the information. We usually take TV and fridge with us for outdoor camping and when the power cut happens it's really too bad and all the electronic items becomes worthless. Therefore, we always take a portable generator from generators sales NJ with us. It is very comfortable to take and use. The best thing that we discovered.