VintageRacer wrote:
The one rule for inverters that is always right is that there is no one rule for inverter use.
My 1000 watt true sine wave inverter purchased on sale @ Canadian Tire for $199 Cdn + tax draws 350 ma in idle mode with nothing plugged into it, draws nothing when it's turned off, which I can easily do with the included remote I mounted inside the trailer. It's also an example why I'd not totally agree with
BFL13's statement -
"Of course there is no sense in having the big one if you are only ever going to use it for small jobs. In that case just get a small one." Here in Canada I found it could actually cost
more for a smaller 300 to 600 watt true sine wave inverter than a larger one so my reasoning was I might as well buy the 1000 watt and be done with it. Sure, inverter quality varies widely and obviously impacts price but to date this 1K inverter I have has done the job with no issues so for me it was a better investment than a smaller but more costly version.
As for idle draw I'd say it varies considerably from inverter to inverter ... I have a 300 watt MSW that idles at 90 ma with nothing plugged into it and draws nothing when turned off. Sure, 90 ma is less than 350 ma but if I'm running with a couple of deep cycle batteries as source power the difference isn't really going to have that much impact. What does make a difference is running each device on the appropriate power source in the first place. A case in point - I normally run an 11 watt 120 vac LED bulb with an E27 base in a table lamp when camping on an electric site, not to save energy obviously but simply because it's the right luminosity, the right colour temperature, and we use a gaggle of the same bulbs in the house. When dry camping I can of course power this LED bulb with my 1K inverter but total draw for just those two devices is slightly under 1000 ma. I also have a 12 vdc LED bulb and because it too has an E27 base can use it instead in the table lamp and power it directly from the trailer's 12 vdc system - similar luminosity, similar colour temperature, but the draw is just 350 ma ... so it's the better "tool" in this case.
With other devices such as my various 120 vac fans I have no choice but to use the inverter when dry camping. Yes, my 300 watt MSW will power any of these fans but they squeal like crazy, enough to be annoying ... but plugged into my 1K true sine wave inverter and they run much as they do on 120 vac shore power. Fan draw on 120 vac shore power is insignificant but plugged into my 1K inverter total 12 vdc draw is considerable, ranging from ~ 3 to ~ 5 amps depending on the fan and it's speed, in which case the inverter's 350 ma contribution is relatively insignificant and IMO doesn't justify using the smaller MSW and having to suffer the squealing. Based on this I tend to agree with
BFL13 that anyone running a reasonable amount of battery reserve would do just as well using just one properly sized inverter that can cover all anticipated needs rather than a gaggle of inverters of various sizes.
