Inverter size

hayray

I have a AC fence energizer that is listed as .2 amps and 25 watts power usage. I want an inverter that is small and won't consumer much power. Pretty dissapointed with the sales department at Northern Arizona Wind & Sun. The salesman I talked too could not give me too much technical information as far as power consumption by the inverter, he said for example there is a 125 watt inverter listed that uses 5 watts on the output side, non of us knew what that meant, he suggested I call the manufacture. If that thing uses 5 watts then I would need a 100 watt panel just to run that. Are there any smaller inverters that I can buy and where can I call to order one? Any advice would be appreciated.

BB.

Re: Inverter size

More than likely, the inverter will consume about 5 watts or 0.4 amps of 12 volts dc with no AC loads.

For a fence charger, it is probably more efficient to find a DC powered charger than to use an AC charger, unless you have other 24x7 AC loads.

-Bill

hayray

Re: Inverter size

Thanks, if that is the case then I might as well forget it and try to get a DC unit. I notice the DC unit of comparable size only consumes 1200 milli amps while this AC unit consumes 2000 milli amps. So I would have to double my solar panel size just to use the AC unit which puts me somewhere close to a 200 watt range and another 100 watts at least for the invertor.

icarus

Re: Inverter size

I agree the DC unit would be a better choice. However, I think you are missing the point of the power requirement of the inverter. If it self consumes 5 watts while powering 100 watts of load for example, you would need to replace the energy of 105 watts, not 200.

Some energy is lost in all electrical conversions, so finding units that self consume the least is an advantage, assuming they are robust enough for your application. The other advantage of a DC unit for example is that you can size the battery and PV accordingly so that you will have power during prolonged periods of no sun.

Tony

waynefromnscanada

Re: Inverter size

Is this an electric fence meant to keep livestock under control, or one intended to kill intruders? This is not a sarcastic question for two reasons. First: When it comes to protecting one's personal property / home, the American way of life, for better or worse, is very different than what Canadian law permits. And second, the power consumption you list is extremely high compared to the many livestock "fencers" I've been involved with / repaired over the years. For now, I'll assume it's for livestock, and if that is the case, definitely get your hands on a 12 volt battery powered "fencer". My Uncle uses them on his farm and finds a fully charged car battery will run them for a good 3 months before he recharges the battery.
There are also solar powered fencers available as a small package.
http://www.oasismontana.com/solar-fencers.html

hayray

Re: Inverter size

This is for livestock, pretty sure it is illegal to put up a fence that could harm people either in Canada or the U.S. Your uncle most likely has some very small fence chargers compared to what I need. This is a 15 stored joule unit using .2 amp, 24 watt power usage. The small complete unit solar fence energizers are very weak and will not run large acreages with heavy loads.