T.V. won't work off Inverter

Sorry for yet another question on Inverters, but I haven't found an answer and there is seems to be some serious experience in the fileld on these boards. 

Facts: The TV in question is a Panasonic CRT that was manufactured in 2001. I installed a 375 watt inverter connected to a DC outlet that was already in place. That combination wouldn't fire up the TV. You could hear that it was trying, but didn't get the job done. So I did some more research. I tested the wires going to the DC outlet and it registered 13.5 volts on my volt meter, so I figured I was getting full power from the Battery. Second I checked the label on the TV to find it was rated at 1.4Amps, so multiplied and doubled for peak power, I was still under the 375. However to play it safe, I upgraded to a 700 Watt inverter with 1800 peak. I removed the DC outlet and direct wired the Inverter using the wires from the pre-existing outlet. Even with the higher wattage, the TV still won't turn on. I'm starting to think that the TV simply will not work with Modified Sine Wave technology. Is there a way to find out? I've checked the Manufac website and can't find anything, probably because of the age.

The only thing I'm trying to do is work a TV and DVD player on the inverter so the kids have something at night to use to unwind before they head to bed. I'm not looking to power the entire rig with it. The only thing I can think of that might work is to direct wire the inverter into the batteries, and run an AC cord to the TV. (The tv I'm trying to power is the one in the overhead above the driver in a class A.

Any suggestions on how to find out if the TV is compatible, or what I might do as a next step, would be greatly appreciated. I would really like to get this working, but I plan on upgrading the coach in a few years, so I don't want to sink a lot of money into it?

Thanks in advance for all your responses.

Most likely the wiring to the DC outlet you are using is not adequate to support the load when the TV is on.  I think that if you measure the DC voltage at the outlet with the inverter/TV on you will find a big voltage drop compared to what the 13 VDC you get with no load.

Ron,

Thanks for the info, as a follow up, would it be worth connecting the inverter directly to the battery, and seeing if that will provide enough power to turn the TV on? I'm willing and able to try anything, just want to get it working even if it is by process of elemination.

That would be a good idea. It would sure let you confirm the TV will operate off your inverter.    For the installation it is better to have the inverter closer to the battery and make the longer wire run with the AC wires.

One of my first attempts to run a TV from an inverter did not work very well. The CRT TV had a demagnetizing coil for the screen which drew a lot of current. Several quick tries switching the TV on and off usually got it working.  Newer LCD TV?s should not have this problem

With my present MH I blew the Dimensions 300Watt inverter by removing the RV power cord from the CG receptacle. I bought a 400 Watt Xantrex RS 400 sinewave unit to replace it. Hooking it up using the original 12 Volt wires would not work. As soon as I turned on the TV,  the inverter would shut down. I tried several places to hook up the 12 Volt power and was unsuccessful until I hooked the inverter direct to the battery with large diameter cables. Further investigation showed that my Itasca Horizon had a 00 cable that ran from the battery in the rear to the Onan generator in the front. I connected the inverter to the end of this cable and everything worked as it should. I then mounted the inverter on top of the generator, rewired the output and everything has worked since. I placed the inverter remote on /off switch in the same place as the original unit.

When I wired up the 12 Volt circuitry I used a boat 100 Amp switch which is available from Harbor Freight for about $6 and an 80 Amp fuse and holder which I got from West Marine for a LOT of money. The dc input power to the inverter can then be switched off when not used.

Wayne

Great info guys, thanks for the responses. If I could, can I ask you to evaluate a proposed fix. Let me know if there is a flaw or safety concern with my plan:

My batteries are in the basement directly below the passenger seat. I'm thinking I can drill through the floor to run cables directly to the battery, and mount the Inverter on the wall next to the passenger seat, as this is an area that is not used regularly (If at all), meaning there is not a likelyhood of it getting bumped or getting in the way. With this positioning, I would be less than 2' away from the battery and if I use Guage 4 wire, I shouldn't loose much in the transfer. From there I can utilize an extension cord from the inverter to the TV and DVD player. In the long run this is a better strategy, because I could then possibly use the inverter for other small appliances if necessary.

So the question is in regards to safety, If I mount the inverter on the wall of the MH, is there a likelihood of the inverter getting to hot and possibly be a fire hazard?  Also are there any concerns with drilling through the floor into the basement, obviously I will fill in the hole once the wires are run with an insulator of some kind.  Finally, the first goal will be to direct connect the inverter to the battery and plug the TV in to see if it will work before drilling anything.

Again, great responses I appreciate all the assistance.

Here is something to think about, 12 volt outlets are rated to around 100-150 watts tops. Anything more than that and they should be blowing fuses.  And the wiring they use is rated 10-20 amps tops for short runs, The run in many a motor home and/or trailer does not qualify as short.

A hunk of wire that drops 2 volts at 10 amps is loosing 1/6th of the voltage

That same wire at 1 amp will loose only 0.2 volts

120 watts at 12 volts is 10 amps

120 watts at 120 volts is 1 amp

Put the inverter as close to the battery as you can get without breathing the same air and use heavy duty cables

Make the run to the TV at 120 volts

BTW,  This is why the power lines up on those poles run thousands of volts.  at 2400 volts, the 200 amp service to your house, if  maxed out, would draw only 20 amps. at 48,000 only 0.1 amp.

Follow up:

I did as you all suggested. I got some 6 gauge wire from Lowes, they didn't have 4 gauge. However, I got 2- 5' lengths which is probably more than I will need, should only need about 2 1/2'. I connected the 5' wires directly from the batter to the 700 watt inverter. I then plugged in the TV and after attempting to turn the TV on 3 times, it finally kicked on, but it was causing such a drain on the Inverter that an alarm of some sort was sounding. So needless to say, I shut it down. The good news is, that I know the TV works off modified Sine, so I shouldn't have to replace it. I'm going to go upgrade the iverter to a 1200 watt and see if that will do the trick.  If it will then I'll go get a fuse to put in the set up and start running wire. I'll make sure to update as I go, in hopes that it will help another beginner at some time.

If anyone has any opinions about the described plan I would love to hear from you, as well as information on how to set up the fuse and if it's going to be necessary to install a breaker. The only thing that will be plugged into this inverter will be  extension cords. I'm not running it through the MH wiring.

In all probablility the alarm you heard was a low voltage alarm from the inverter.  The wire size you used is marginal for the current draw of the inverter and/or the battery could not take the load and dropped the voltage which along with the drop in the wires caused the inverter to alarm.

Have the battery checked and use larger wires for the new inverter.

Like Jim said I think your DC wires to the inverter are still  likely inadequate or the battery is not up to par.

When looking for heavy duty wire to hook up the inverter with LOWES is not the place to go

Auto Zone,  Pep Boys, ____ AUto parts (Fill in the name of your choice)  That is the place to go

Minimum hook up for an inverter between 200 and 750 watts is battery cable or starter cable  (Starter cable is the same save both ends are eyelets, not one eyelet and one battery clamp) both are on the same rack at all the above stores.

This has not been discussed in previous if so I apologize. I have an inverter that requires the plug going into it to have a ground. Some things on my inverter won't work, one of those is a skill saw. I have fooled it by using one of those hand held drop lights that has a plug in the handle. For whatever reason the skill saw won't work by itself. When I use the drop light and plug the saw into it I'm good to go.

So check into this and try putting a surge protector or one of those drop lights in first.

Just and idea...

A couple of suggestions:

Most inverters have fans to cool them which run constantly when the inverter is on and the bigger ones sometimes are a little noisy.  I don't think you want to install one on a wall inside your RV because of the noise.  On the other hand, you don't want to install the inverter in the same basement compartment as your batteries either, unless your batteries don't give off gas (i.e., you have AGM batteries).  So my suggestion is to install the inverter in a basement compartment adjacent to the battery compartment.  Drilling small holes through your basement compartment wall should still allow the cable run from the battery compartment to the inverter to be just a few feet.  Mount the inverter (and in-line fuse) either on the back wall or the side wall of the adjacent basement compartment as close to the battery compartment as possible.

And you DO have to worry about the inverter getting hot, so you should mount it in a way that it has lots of free space all around it and plenty of air available to keep it cooled by it's own fan.  If mounted in an airtight compartment, you will want to consider some way to allow fresh air to get in there without letting in dust and moisture.  (Leaving the compartment door cracked open while using it might be one way.)

Then you will need to run an AC line from the inverter through the floor to the area of the TV.  I would think a 12 gauge 3-wire AC cord would be adequate for anything up to a 1200 watt inverter.  The AC cord could be one with a light built into the female plug that comes on whenever the inverter is on, and should remind you that the inverter needs to be turned off when it's not being used. 

One disadvantage of this type of installation is that you will have to go to the basement compartment to turn the inverter on and off when you want to watch TV.  And you'll have to remember that the inverter will always have power to it, despite the setting of the disconnect switches.

Another suggestion is to order an inverter cable kit (Sam's Club online is one place) to get the right sized cables for your particular inverter.  These cables are long enough for this type of installation, and come with connectors and an in-line fuse for the inverter it was designed for.  (You don't have to order the inverter to buy the inverter cable kit, just be sure the kit you buy fits the inverter you have in terms of cable size, fuse size, and connector size.)

The 1200 Watt Xantrex units have a remote switch available which can be mounted where it is convenient for you. As I suggested before, buy one of the battery disconnect switches at Harbor Freight for about $6 to remove the primary 12 Volt power when the RV is stored. The switches are good for 100 Amps which will give about a kiloWatt of power.

Wayne

What Rolf said.

My install the batteries and the Prosine 2.0 are in the same compartment but the batteries are AGM and are boxed next to an exhaust fan, the fan comes on at 90F,  The fan in the inverter is also temp senestive though I do not know the temp setting.

I cut two 4" holes, put a computer type 12vdc van over one with the 90degree switch, and outside (this one blows in between the two compartments) I shoved an automotive air filter to keep bugs and dirt from coming in the "out".

I cut a 2nd hole directly behind the inverter's fan and also bolted a air cleaner over that hole, making a "Filter sandwich" with 4 long bolts that come out from inside the compartment, the filter nestles within the bolts and a piece of plywood is then bolted on the other side,  Thus all air entering/leaving is filtered for bugs and rocks and such  So far it looks good.

As for cut off switches... I have a collection of knife type battery selector/cut off switches in that rig.

They are rated 400-700 amps SWITCHING and higher than that if they do not have to switch.  I have no doubt that the 800 amp OH C**P fuse would blow before those switches would suffere serious damage from over load.

I tube TV might "run" at only 300 or so watts, but to get it going will require a momentary (few seconds) "surge" current much greater than that.  1000 watts or so doesn't sound out of line.  For a generator (or household 30 amp circuit) that surge isn't a problem, but an inverter most likely has circuitry that doesn't allow this "surge" over it's rated output (or perhaps it has a surge-rating, but it's not high enough to accomodate the TV.

As for the inverter location wiring question... you're better off having a short DC run, and a long AC run.

I have run fairly large TV's off a 1KW MSW inverter.

I have run smaller ones off smaller inverters  I used to run about a 15 inch monitor off a 450 inverter but it was monocrome and those don't have the big surge that color units have.

Guys, thanks for all the comments and suggestions. Based on all the feedback, I've redesigned my configuration as follows.

I ordered a 1750 Watt Inverter with 3' #0 gauge wire. The basement compartment that my batteries are located in are seperated, so that the battery area on the bottom is open for air circulation, then above it there is another platform that is sealed and weather tight for storage.  The plan is cut a hole in the platform between the two for the wires to run through and mount the inverter above the batteries. Obviously sealing the hole once the wires are through.  Then I will run an AC line through the floor into the living space to run up to the TV and DVD. The nice thing about the inverter I purchased is that it has a remote on/off switch that I can mount in the living area. I was actually thinking about using a surge protector for the initial AC run, one that has a lighted switch so I can tell if the inverter was left on, since the remote switch does not have a light.

So, here lies the next question in my quest for keeping the kids happy. From the battery to the inverrter, it's been mentioned to use a fuse or battery disconnect switch of some sort. Since the wire is going to come installed with the eye let connectors on the ends, do I want to splice it to put an in line fuse on, or what is the suggested method.

THE GOOD NEWS: I'm hoping to have this thing up and running this weekend, so you only have a few more days of bothering with all the questions. i just want to do it right and make it safe and the only way I learn is by asking questions and doing it myself, so thanks in advance for all the help and suggestions.

Shadowman said:

...it's been mentioned to use a fuse or battery disconnect switch of some sort.

Click to expand...

I'd suggest you use both.

.... do I want to splice it to put an in line fuse on, or what is the suggested method.

Click to expand...

They really need it to crimped or soldered. Take a look at the photos in this article in our library. Although it was a larger inverter and larger wires, the same kind of fuse and switch would work, although your fuse rating would be lower.  *

A 1750 watt inverter looks like overkill for just wanting to watch TV.  The bigger inverter you get, the more things you'll find to run off of it, and the faster you'll run down your house batteries.  A 1000 watt inverter should have been plenty big enough.  But either way, it looks like you are going to need a disconnect switch AND an in-line fuse.  The disconnect switch will be used to shut the inverter down completely so that even the remote control function will not work.  You should use the disconnect switch to disconnect the inverter whenever you won't be using the inverter while you are NOT connected to shore power and NOT running your generator.  Even little battery drains like the inverter remote control end up running batteries down over time.

The in-line fuse is definitely a safety requirement.  Looks like you'll need a pretty big one for a 1750 watt inverter.  Your inverter manual should tell you specifically what size fuse you'll need.  My suggestion is, don't splice the current cable you have, get another very short one (already manufactured) to run from the fuse to the inverter.  (If you're like me, crimping connectors on #0 gauge wires is not something you really want to do yourself.)

Have you thought about how you are going to ventilate the inverter compartment?