Inverters are electronic devices that convert direct current (DC) to alternating current (AC).

There are two basic types of inverters. They are,

• True sine wave Inverters (TSW).
• Modified sine wave inverters (MSW).

The True sine wave inverters are either transformer based (for example, Trace SW series) or High Frequency (for example, Statpower prosine).

Likewise, the Modified sine wave inverters are also either transformer based or High Frequency.

The sine wave Inverters are further classified into,
 Stand alone.

•  Utility tied central inverter with Backup Power that they charge a battery bank.
•  Utility tied central inverter without Backup Power that is they are battery less.
•  Utility tied Micro Inverter.

Sine Wave Inverters

A true sine wave inverter (TSW) replicates and improves the quality of electricity supplied by the utility companies. Sine wave inverters are used to operate high-end electronic equipment.

Description and Uses of sine wave Inverters types:

sine wave High Frequency Inverter
The sine wave high frequency inverter can operate smaller to larger units. This type of inverters can be used when small motors are required to operate moderate loads like those occurring in circulator pump. These inverters can also be used in situations where portable sine wave power is required or in places where the space is less.

sine wave Transformer Based
The sine wave transformer based can operate medium to larger units. These types of inverters are required for net metered installations. This is also used in large RV's and boats.

Central Inverter without Backup Power
The central inverter without backup power is used in utility tied system over 600 watts that do not require backup power. This is an inexpensive source of PV power for net metering.

Micro Inverter without Backup Power
The micro inverter without backup power is used in utility tied system under 600 watts that do not require backup power. This is also an inexpensive source of PV power for net metering.

Advantages of sine wave Inverters and Types

sine wave Inverters in General

• sine wave inverters operate any type of device that can be operated by the utility companies which is subject to maximum load restrictions.
• Some sine wave inverters generate power that is accepted for selling back to utilities which falls under Net Metering programs.

Microwave Inverters

• The micro inverter can be sized exactly to match the PV panels.
• The micro inverters are easier to install as they require only AC wiring

Central Inverters

• The central inverters are inexpensive when installing in larger systems
• The central inverters are more efficient

Guidelines to use the appropriate inverters

• When using a device that senses either peak voltage or zero crossing, it is advised to True sine wave inverters as running them on modified sine wave inverter could result in various problems.
• When using sophisticated audio systems, remote measurement equipment, surveillance or telemetry equipment it is good to use True sine wave inverter.
• or transformer less chargers, garage door opener, laser printers it is better to use True sine wave inverter. When, modified sine wave is used with transformer less chargers they are likely to damage it.
• Modified sine wave inverter works fine with a product that operating through an AC adapter. For example, laptops, video games, cell phone and digital camera chargers.

True sine wave inverters has the following advantages over modified sine wave inverter,

• There is very low harmonic distortion in the output voltage waveform of TSW and the power produced is similar to that of utility companies.
• The usage of TSW reduces noise in audio amplifiers, TV etc.,