A power inverter converts DC (Direct Current) power from your solar or wind charged battery into AC (Alternating Current). Anything that plugs into a wall outlet in your home runs on AC.
RV (Recreational Vehicle) power inverters are designed for use with RV mounted solar panels. Having an RV solar power system is like having a mini onboard power plant. It allows you the freedom and flexibility to camp out where there is no conventional power source; what's commonly known as living off the grid.
The key to portable solar powered success is investing in a properly sized power inverter. As with everything else, when you purchase an RV power inverter you get what you pay for.
A well made power inverter should be efficient at all input levels, rugged enough to stand up to changing environments and won't overheat while providing the power to run your small appliances.
Various brand name inverters include Outback, Magnum, Xantrex and Go Power. Choosing and installing a properly sized inverter is a task best left to your local RV professional or alternative energy store.
In order to pick out an RV inverter perfectly suited to your needs, you will have to provide your local professional with some basic information.
You need to know what appliances are going to be powered with the system, how much power they
consume (amp/hours), and the phantom load.
Phantom load is the electricity consumed by an appliance when it is turned off. Your television set is one example, but the worst offender is that cube shaped transformer used to charge cell phones. These transformers are 60% to 80% inefficient and should be unplugged when not in use.
The power consumption of each appliance is stated somewhere on the appliance itself, and is expressed in terms of AC watts or AC amps. What the RV owner really needs to know is the equivalent in DC amps, since that's what the battery bank is supplying.
Where an appliance's power consumption is expressed in terms of AC watts, one can use a simple formula to calculate the equivalent power expressed in DC amps:
DC Amps = AC Watts / 12 volts
Example: A TV set with a 100 (AC) watt rating used for one hour would consume 9.17 DC amps.
Look for an inverter with three distinct charging rates: a bulk charge at 100 amps; then dropping to a lesser rate as the voltage increases in the battery bank; and finally applying a float charge just sufficient to maintain the batteries in a fully charged condition. The result is much faster recharging of the batteries, either from shore power or from the motor home or tow vehicle alternator.
A good quality solar panel can deliver approximately 3 amps of power during daylight hours. A conservative estimate for sunny weather might be 6 hours of full solar power per day and somewhat more during summer months. Thus one panel would put roughly 18 amps back into the batteries; 2 panels 36 amps; and 3 panels 52 amps.
The remote monitor and control mechanism mounted inside the coach performs a wide range of functions pertaining to both the inverter and charger functions. It also has the basic "on/off" switch for the inverter.
When "on", the control panel provides information about whether the unit is operating in inverter or charger mode. If operating in the inverter mode it will tell you the present level of amps being consumed and the present voltage under that load.
If in the charger mode, it shows the present level of the amps in, along with the voltage at which it is being charged along with various warning functions pertaining to overheating and overloads.
Clearly this is not a "one size fits all" choice. Especially important is the need to consider your RV lifestyle when determining whether or not an inverter would be a useful resource.
