Frequently Asked Questions about Power Inverters
A power inverter changes direct current DC from a battery into conventional alternate current AC that you can use to operate all kinds of devices (electric lights, fans, kitchen appliances, TVs, radios, computers, to name just a few). You just connect the inverter to a battery, and plug your AC devices into the inverter … and you’ve got portable power … whenever and wherever you need it. The inverter draws its power from a battery bank. The battery will need to be recharged as the power is drawn out of it by the inverter.
We carry many different sizes, and several brands of power inverters. See our Inverters Page for specifications on each of our models.
Short Answer: The size you choose depends on the combined load (find the power consumption by referring to the specification plate on the appliance or tool) to be powered. We recommend you buy a larger model than you think you’ll need (at least 50% more than your total load).
Example: You want to power a computer with a 17″ monitor, some lights, and a radio.
|2 – 30 Watt lights:||60 Watts|
|Total load:||250 Watts|
For this application, you would minimally need a 500 W inverter
Advantages of Pure Sine Wave inverters over modified sine wave inverters:
- a) Output voltage wave form is pure sine wave with very low harmonic distortion and clean power like utility-supplied electricity.
- b) Inductive loads like microwave ovens and motors run faster, quieter and cooler.
- c) Reduces audible and electrical noise in fans, fluorescent lights, audio amplifiers, TV, Game consoles, Fax, and answering machines.
- d) Prevents crashes in computers, weird print out, and glitches and noise in monitors.
- e) Reliably powers the following devices that will normally not work with modified sine wave inverters:
- Laser printers, photocopiers, magneto-optical hard drives
- Certain laptop computers (you should check with your manufacturer)
- Some fluorescent lights with electronic ballasts
- Power tools employing “solid state” power or variable speed control
- Some battery chargers for cordless tools
- Some new furnaces and pellet stoves with microprocessor control
- Digital clocks with radios
- Sewing machines with speed/microprocessor control
- X-10 home automation system
- Medical equipment such as oxygen concentrators
Batteries are capable of supplying large amounts of current, and thousands of amperes could be present if a short circuit were to occur. A short circuit can damage your system, cause a fire and be hazardous to your health. Incorporating an overcurrent device is an effective line of defense against a short circuit occurrence. An overcurrent protection device is typically a fuse or circuit breaker that goes inline on the positive cable, between the inverter and battery, to protect your system. A fast acting fuse or circuit breaker will blow within milliseconds under short circuit conditions, preventing any damage or hazards.
It is important to appropriately size your fuse or circuit breaker for both your inverter and cables. An oversized fuse could result in cables exceeding their ampere capability, resulting in the cables becoming red-hot and dangerous. Consult your owners manual for the recommended sized fuse or circuit breaker and cable gauge for a safe installation.
500 Watt and larger Inverters: We recommend you use deep cycle batteries which will give you several hundred complete charge/discharge cycles. If you use the normal vehicle starting batteries they will wear out after about a dozen charge/discharge cycles.