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DaleM · 08-24-2014, 11:12 AM

I need some input into an inverter wiring question.
I have a 40 ft 5th wheel, the TV is against the rear wall. I want to be able to watch TV at night without running my honda
Generator..
Here's where I'm at, I have a 1500 watt inverter with a wired 6ft remote.I'd like to power ONLY the TV and DVD system with this inverter. In order to mount this wired remote somewhere useful would mean the inverter power wires going to the battery would need to be close to 12ft long.I have enough welding cable to run that span. I know it a very long run but it's only going to power the entertainment so the draw is going to be Minimal. I don't want to have a 20 ft extension cord along the floor or wall to get to the TV, so here's a thought, the inverter if I mount it where I'd like would be very close to the main fuse/breaker box, was thinking I would take the wires off the breaker that run to the TV power outlet and plug this into the inverter that way I don't have to run new wires to the TV.. I could switch the inverter on and off from the remote,
Could it be left on while charging. I don't know why not, there is no loop going from the inverter back to the batteries,
I don't want to go the automatic transfer switch route to only watch TV.
Your thought please
Thanks
DaleM

Skip426 · 08-24-2014, 02:50 PM

Welding cable could be over kill, JMHO. You inverter instructions may provide a wiring size per length table. You'll want a 12v circuit breaker within a foot or so of the battery to protect the cable against shorting out.
The inverter can be left on while charging.
If size, of the inverter, for the chosen location proves to be a problem, original equipment on my coaches , entertainment center , ( CRT TV) was 400 watts,( now have 600w, pure sine wave) and the new flat screens don't use much power , I run a DVR, and 32" flat screen and never tax the inverter.

BFlinn181 · 08-24-2014, 03:02 PM

Skip426 voices the same question I had reading your post. 1500 w is a bit of overkill for a TV and DVD. I'd add up the watts needed for the two items and invest in a pure sine wave inverter a little bigger than required. Inverters consume battery power while changing 12 v DC to 120 v AC and bigger ones consume more. Getting an inverter properly sized will save battery capacity and allow the movie to run longer. In addition, a pure sine wave inverter will play nicer with the electronics.

You could either sell the 1500 w inverter or install it for kitchen use. It can power your microwave, toaster, or coffee maker. (not at the same time)

vsheetz · 08-24-2014, 03:07 PM

I use a 150w inverter for a 32" TV and blue ray player. The new equipment does not take much power.

nothermark · 08-24-2014, 03:16 PM

In general you want the inverter as close as is reasonable to the 12V source. A 1200 W load would draw ~100 A @12 V to feed the inverter. The output would be ~ 10 A. Power loss is a function of the current squared so the lower the current the better. That is why they do high voltage distribution. ;-) You want to check the power draw of the TV and DVD system. If it is only a couple hundred watts (quite possible) it could be worth downsizing the inverter. Smaller feed wires and less loss in the inverter.

DaleM · 08-24-2014, 05:00 PM

Hi again
Yes I know the 1500 watt inverter is huge over kill but I have it doing nothing and I like the idea of the remote to turn it off.
I thought about also wiring it in to run the microwave but I don't want to have the microwave running throw the inverter when I'm plugged into shore power,
I thought about a Small inverter installed right by the TV, there are 12 volt wires right there that run the TV lift and I could
Splice into them, but they are 14 gauge and are 30 feet from the power panel and I thought it might be too much of a draw on small wires, the Tv is a 42 inch samsung and a samsung sounds around system with a powered sub woofer.
Dale M

wa8yxm · 08-24-2014, 05:09 PM

I do agree that in general you want the inverter close to the batteries, but.. You are looking at a less than 500 watt load and cable that can carry easily 100 amps (that is over 1,000 watts) so I'd say go for it..

HOWEVER.. I would look for a smaller inverter.. Peak effiency on most inverters is around 90%, does not matter if MSW or TSW (I used to think it did till someone ask a question that made me research it, thank you questioner) but you will see that rate near full load. At a light load the efficiency goes down, WAY down.

IF the inverter is a True Sine Wave, use a Kill-a-watt to see what the load is, get an inverter in the 2x K-A-W VOLT-AMP reading range.

Cypressloser · 08-24-2014, 05:57 PM

I agree with others saying you need a 12 Volt fuse close to the batteries, in your case probably 200 Amp.
The remote cable on the on/off switch is likely a cat... cable, it would be very easy and cheap to make one up that lets you install the remote in a convenient place and still install the inverter close to the batteries, computer stores can do it or you can buy wire and a crimp tool at HD or Lowes. Just make sure when you have open cell (vented batteries) that the inverter and fuse can not be in the same compartment.
Don't underestimate the importance of wire size and voltage drop, a 10% drop is not acceptable for an inverter. You will get some line loss, try to keep it below 3%, some inverters shut down when they receive less than 11.8 Volt. Here is a link to a chart http://assets.bluesea.com/files/reso...on_chartlg.jpg

1mainiac · 08-24-2014, 06:13 PM

I agree 1500w is over kill but if you already have it you can use it. I assume the inverter does not have internal transfer so it is invert only. I would wire it with a small transfer switch so you can go from shore to inverter and I would pick up the kitchen or micro wave circuits as well. Hot coffee or popcorn might be nice while watching a movie.

Cypressloser · 08-24-2014, 07:52 PM

Quote:

Originally Posted by 1mainiac

I agree 1500w is over kill but if you already have it you can use it. I assume the inverter does not have internal transfer so it is invert only. I would wire it with a small transfer switch so you can go from shore to inverter and I would pick up the kitchen or micro wave circuits as well. Hot coffee or popcorn might be nice while watching a movie.

Was thinking that but didn't dare to spell it out