Laptop computers, cell-phone chargers, coffee makers and similar-sized appliances will operate efficiently on inverters ranging from 200 to 800 watts. These compact- to mid-sized inverters fit in cup holders, console storage compartments and glove boxes, making them a good choice for general use while traveling.
Larger inverters (1,500 to 2,500 watts) should be professionally installed, as they are intended to provide power to large appliances in RVs. Wiring in these large units requires a high degree of skill and patience, and, if done incorrectly, could become a potential fire hazard.
Continuous/peak power is used to describe the power capability of an inverter.
Continuous power is the constant draw that an appliance puts on an electrical system. Peak power is not constant, and is often referred to as "surge".
Peak power is most often encountered during appliance start up (we've all seen lights dim when a refrigerator or dryer turns on), and must be taken into account before deciding on a power inverter.
Not sure of the power your inverter application will require? Use this simple formula: Volts x amps = watts.
In this formula, you only need to know two of the variables to calculate the third.
For example, you may want an inverter to power a coffee maker. The coffee maker is 120V and requires 6 amps of current. By multiplying volts and amps, it can be calculated that the coffee maker will require 720 watts of power.
Knowing the wattage required, you can purchase an inverter with confidence, knowing it will meet the needs of your electronic accessories.