inverters

smallpond3500 · 11-08-2011, 05:42 PM

We going to buy a inverter for 1990 HR HAS MICOWAVE and tv What would be best Useing 4 6volt batteries

Paul R. Haller · 11-08-2011, 05:56 PM

I'm sure I will get other opinions that differ from mine but I'll offer one anyway. I like having a larger inverter. It allows you freedom to have whatever you want on at the same time say, a microwave and a coffee pot in the morning or the satellite tracking, TV, and dvd at night. I also see no need for a full sine wave inverter as all my appliances work fine with a modified sine wave inverter and they are 1/3 the price of a true sine wave inverter. All that said I would opt for a 3000 watt modified sine wave inverter located in cabinet apart from your batteries and connected to them with a 4/0 wires and extra heavy duty lugs no longer then 24 inches. With this set up you will have the freedom to hook up anything you want otr even better an outlet supplied by the inverter for the whole coach.
-Paul R. Haller-

JimM68 · 11-08-2011, 07:14 PM

I agree with PAul about the modified sign too, never ran into anything that didn't work just fine with it.

Not so sure about a 3000 watt inverter in a 4 battery coach though. Mine has a 2000. It will run the coffee pot and hairdryer together, along with a tv and the satelite dome, not a problem till you look at the ammeter... Pulling 200 amps out of the batteries is just plain scary.

Ed-Sommers · 11-09-2011, 09:10 AM

A 2000 watt sine wave is what I recommend. I used to be one of those that believed that modified sine wave was just fine till I got a true sine wave. Reasons are - anything that produces heat, directly, like a coffee maker will probably burn out sooner, the microwave will run hotter, and at diminished power. TV heat output is higher with MSW, Ect.....All in my opinion, but with experimentation.

Ed

wardy · 11-09-2011, 09:29 AM

Anything that has a transformer or AC motor will run hotter. Resistive loads like a coffee pot will be fine for the most part . Try running a compact florescent bulb with a modified sine wave inverter as an example. After a few minutes feel the ballast and you'll find they run WAY hotter than clean AC.

wa8yxm · 11-09-2011, 11:07 AM

I too would suggest a 2,000 watt TRUE SINE WAVE.. And in this case I do in fact take my own advice.. that's exactly what I use in this motor home.

srydve · 11-09-2011, 11:12 AM

Here is some useful reading before making the decision as to what type of inverter LED Night-light fire

wa8yxm · 11-09-2011, 02:38 PM

Let me put it this way.. Xantrex used to have a document on the X-Power (MSW) inverter support page with a title something like "Things that might not work properly with MSW inverters"

I have a prosine (True sine wave) no such document on it's page.

The reason is simple..... The power out of an MSW inverter has a lower (but longer) peak.. If you do all the very complex math (Best done by a meter) you find the "Area under the curve" of the signal trace is identical so the RMS voltage is the same, but the peak is lower.. Devices (many power supplies for Televisions, radios, microwaves and the like) rely on the PEAK voltage.

Second it contains harmonics.. IN theory it's either all even or odd, (I forget which) all the way up to Microwave, in practice they do manage to filter a lot of that. But I've seen quite a few that get well into "Television" frequencies,, Some.. Well some once you get past AM broadcast are no longer objectionable.. But at AM broadcast they are very clearly there.

These harmonics also mean digital timers that use the power line as a source may be fooled, Some voltage dividers may not divide properly (LED Night Light Fire) and other issues may crop up.

That said... In many cases they work just fine.

Oh the list of things that won't work properly with a True sine wave inverter:
Anything needing more power than it can produce.. (end list)

John Hilley · 11-09-2011, 04:39 PM

I also would recommend a 2000 watt true sine wave inverter. My last motor home had a 1500 watt modified sine wave and every thing did run fine. I now have three pure sine wave inverters, a 2000 pure sine wave for general use, a 1000 watt pure sine wave for the TV and satellite receivers and a 180 watt pure sine wave for printer and notebook charging. The 2000 watt is used for the kitchen and bathroom. The 1000 watt inverter has a remote control so it can be turned on or off from the bedroom.

ottffss · 11-09-2011, 04:59 PM

Quote:

Originally Posted by JimM68

I agree with PAul about the modified sign too, never ran into anything that didn't work just fine with it.

You might want to reconsider... You have just been lucky. MSW DOES cause significant problems for some electronics. See this thread. Keep reading it to find out the not so well known side of MSW.

LED Night-light fire