Q/A

• What are inverters and do I need them?

  Inverters turn the DC output collected from your solar panels into alternating current (AC), which is the standard used by all commercial appliances. Inverters serve as the gateway between the photovoltaic system and the devices and appliances drawing energy from your solar panel system. You’ll typically need an inverter for any solar panel larger than five watts.

• What is the difference between pure sine wave and modified sine wave inverters?

  When shopping for an inverter, there are two main options to choose from: pure sine wave and modified sine wave inverters.

• Pure Sine Wave Inverters:

  Pure sine wave inverters are capable of producing smooth, quiet, and reliable electricity to operate appliances and electronics without any interference. Like its name suggests, pure sine wave inverters produce current in a pure sine wave shape. Renogy sells a range of pure sine wave inverters of varying capacities to fit your solar installation and energy needs. Renogy inverters also provide overload protection for both DC input and AC output to prevent damage to the components and the unit.

• Modified Sine Wave Inverters:

  In modified sine wave inverters, the polarity abruptly switches from positive to negative versus a true sine wave. When looking at the wave, it has a stair-step, square pattern, where the polarity is flipped back and forth. That choppy wave can negatively affect more delicate, sensitive equipment. If you have medical equipment you need to power, such as a CPAP machine, you won’t be able to use a modified sine wave inverter. Additionally, in many cases, you’ll hear a hum with devices attached to a modified sine wave inverter. However, with simple devices and appliances, modified sine wave inverters typically do the job.

• What do I need a pure sine wave inverter to run?

  As noted above, you need a pure sine wave inverter to run appliances with AC motors, such as microwaves and refrigerators; medical equipment, such as CPAP machines with humidifiers, sensitive electronics, laser printers, newer TV’s, and appliances with electronic timers or digital clocks. Your laptop may work with a modified sine wave inverter, although some claim that using one can shorten the lifespan of your laptop’s battery.