How to Select DC to AC Inverters

DC/AC Pure Sine Wave Inverter. Image Credit:Analytic     Systems Inverter  Image Credit: Digi-Key

DC to AC inverters are used for converting direct current (DC) into alternating current (AC). They are also known as DC to AC converters.

About DC to AC Inverters

DC/AC power inverters convert DC power from a battery or other power source (mostly 12 VDC) to standard household AC power (110VAC). Inverters use oscillator circuts to accomplish the inversion through a series of steps. The DC circuit flows down one end of the circuit with an electromagnet. When the current hit a magnet, the magnet activated and the current flow would change to the other side of the circuit cutting power from the electromagnet.

Product Selection

The GlobalSpec SpecSearch database allows industrial buyers to select DC to AC Inverters by type input values, output values, and options.  

Inverter Types

DC to AC inverters can be one of several different styles.  These include princ circuit board mount, or card mount, laboratory bench or portable configuration, rack mount, DIN rail mount, wall mount, and stand alone or tower mount.

Input Values

Nominal DC input values for DC to AC inverters can be 12 VDC, 24 VDC, 48 VDC, 110 VDC, 125 VDC, an 250 VDC. 

Out Values

Important output specifications to consider when searching for DC to AC inverters include,

• Maximum voltage
• Maximum steady state current
• Maximum power
• Frequency range

Waveform output choices include,

Wave Examples. Image Credit:Wikipedia

• Pure sine wave is the best waveform, as it is the shape of an (ideal) AC electrical signal from the wall. The highest-quality inverters produce a true sine wave output, which requires fairly expensive components in the inverter. True sine wave outputs are normally found only in higher-end models.
• Square wave is sort of a "flattened-out" version of a sine wave. Instead of the voltage smoothly increasing from the negative maximum to the positive maximum and back again, it shifts suddenly from negative to positive, stays there for half a cycle, and then jumps to full negative and stays there for half a cycle, then repeats.
• Stepped wave is a quasi-square wave or sine wave - they are typically inexpensive power inverters that mimic a sine wave using a stepped waveform. The output waveform signal changes abruptly from zero volts to a maximum value, them abruptly again to a zero value. After a short off time, the signal then switches abruptly again to a maximum negative voltage and then abruptly again back to zero.
• Triangular wave is sometimes referred to as a saw tooth wave for its approximation to a saw blade.

Options

User interface options for DC to AC inverters include,

• Local interface can be
  • Analog front panels with
    • Potentiometers
    • Dials
    • Switches
  • Digital front panels with digital keypads and menus

• Computer interfaceoptions include serial or parallel interfaces.
• Application software is used for control or for monitoring converter performance.
• Display type
  • Analog meter or indicator
  • Digital readouts
  • Video display terminals.
• Forced air or fan cooling
• Battery charger
• An important environmental operating parameter to consider is operating temperature.

Applications

DC-AC inverters can be used in a wide range of applications including,

• Computer
• High frequency
• High voltage
• Instrumentation
• Laser
• Magnetic
• Medical
• Military
• Plasma
• Telecommunications

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