Invertor and TV Question

cliff841 · 04-26-2011, 01:22 AM

My coach did not come with an invertor. I was going to have one wired in but realized it was very expensive. All I'm looking to power is the front TV and a DVD or blu-ray player. Would a 300 watt model that plugs in to the 12 volt jack do the trick? What would happen if it is not enough power?

Any other suggestions on how to handle this? I just want to be able to watch TV or a movie after quiet hours.

texnet · 04-26-2011, 08:19 AM

Look at the back of the TV and DVD player. You will find a label that will tell you how many watts is required for each item. Purchase an inverter with about 25% more power than is required for the sum of the two items.

wa8yxm · 04-26-2011, 09:42 AM

Yes, and no.. A 300 watt model will likely do the trick, Try to get a TRUE SINE, since they work better with receivers.

But plugging into the lighter socket won't.. you need to wire it direct to the battery, Put it nearby, hook up with starter cables (lone red one black) but do not put it in the same "Air Space" as the batteries (you do not want to breath battery fumes) run some 120 volt wiring from the inverter to the TV area. make the outlet it feeds RED or ORANGE (denotes emergency power)

BigV · 04-26-2011, 10:02 AM

Only way to know what you need is to measure. Pick up a device called a kill-o-watt. It will show you what your needs are.

My Visio LED tv draws 30 watts and my blueray 20. I could run those on a 100 watt inverter.

True sine inverters are more efficient and small ones are not much more than the cheap ones. Camping world usually has a coupon to get the Xantrex Prowatt SW 600 for around $150. One of those would run most anything short of a microwave or toaster.

Wanabee FTer · 04-26-2011, 10:28 AM

wa8yxm and BigV are right. Get a 600 watt pure sine wave inverter. I installed the Xantrex SW600 as mentioned above. Try to mount 3'-5' away from batteries. I went to wally's and bought two 2 gauge starter cables and then went to a stereo install shop and bought an inline 80 amp fuse. Mount the fuse on the positive wire as close to the battery post as possible. I mounted the inverter under the dash (behind the firewall) and use a HD extension cord if needed. You will find yourself using the inverter for more then just the TV and DVD so it is a good idea to get a little bigger unit then you think you need. If you get anything over 600 watts expect it to draw more amps from your battery bank to operate the inverter.

cliff841 · 04-26-2011, 08:27 PM

Thanks for the info. I will try to get a 600 watt sine wave invertor and wire it up.

BigV · 04-27-2011, 07:03 AM

Mine is mounted under my dash as well. I have a 2k inverter and used 2/0 welding cable. More flexible. I used a Moroso bulkhead power connector to pass the power through the firewall. The ground wire just has a bolt that goes through the firewall.

Another fuse option to consider is called a battery fuse. You can get them online but I picked mine up at a boat shop. The fuse mounts directly to the battery post. I like those better than inline fuses.

dirko · 04-27-2011, 06:09 PM

Hi Ho: Well, we did just what you have in mind about 10 years ago and it still works just fine. We did have a 300 watt inverter and just simply added another. We find that there is no detectable difference between sine wave and clipped wave (at least for us). You do have to consider how much power you need and size both the inverter and the primary wires accordingly.

One advantage to the inverter that came with our MH is that it has automatic switchover so that you don't have to do anything when going from 110 volt power to inverter power. This model also has low voltage cut-off which is really a good thing because it prevents you from taking too much power from the batteries and shortening their life. I believe it cuts off at 11.5 volts which is just fine because there is about a 0.5 volt drop in the primary wire and 12.0 volts is where we prefer to stop discharging the battery. For us that is about 4 hours of TV, DVD, audio receiver and amplifiers.

Anyway, just because someone says approach X works for them doesn't mean that it is best for you. We don't know how much battery capacity you have or how much power drain or for how long. These are the parameters that you need to design your system.

Dirk