A fan will either be powered using alternating current (AC) or direct current (DC), and each current has a different set of voltages (V). An alternating current fan will have a voltage rating above 100 such as 110V or 240V. In contrast, a direct current fan will have a lower voltage rating such as 5V or 48V. A fan will have exactly one current and one voltage, examples include AC 115V, DC 24V, and AC 220V. The current and voltage can also be written together such as an AC 120V fan might be stated as 120VAC. The information below will help you identify the proper current and voltage.
     Voltage Range: Higher voltage ratings above 100. Common     Voltage Range: Lower voltage ratings below 100.
  AC voltages include 110, 115, 120, 220, 230, 240   Common DC voltages include 3,5,12,24,48 
  Construction:  Case is usually made from die cast aluminum   Construction: Case is usually made from thermoplastic
  Connectors: Most have terminals [male two-pin connectors] or   Connectors: Most have two to three wires. Black and red
  two black wires   being the color of the first two wires
  Power Source: Can be powered directly through an electric   Power Source: Typically powered by a power supply,
  outlet. Sometimes a step-down or step-up transformer is used.   converter, or transformer thats connected to an outlet. Also
  North America uses 120V and Europe uses 230V standards.   can be powered by batteries.


AC Fans


110V to 120V: AC fans that run on 100 to 120 voltages such as 110V or 115V have fundamentally the same power input. This is because fans are designed to tolerate a range of voltages. So a fan might state 110V on its label but it will be able to run on a 120V power source. The speed of the fan can also by controlled by reducing the voltage input. However, voltages above the fans range could damage it. The standard electric outlet in the United States is 120V and will be able to directly power fans that have 120V within its range such as 110V, 115V, and 120V AC fans.

220V to 240V: AC fans that run on 200 to 240 voltages such as 220V or 230V have fundamentally the same power input. For example, a fan might state 220V on its label but it will be able to run on a 230V power source. Europe uses 230V as its standard for electricity. As a result, fans that run on 200 to 240 voltages are typically found in foreign imported equipment that was not designed specifically for the US market. If a US resident wished to directly plug a 230V fan in an outlet, he or she would require a step-up transformer to convert the outlets 120V to 230V.

DC Fans


3V, 5V, 12V, 24V, 48V: DC fans come in standard voltages including 3V, 5V, 12V, 24V, or 48V. Because the electricity grid that powers homes and businesses provides AC electricity, DC fans cannot be powered directly by an electric outlet. A DC fan is usually connected to a converter which is then plugged into the outlet. The converter will receive AC 120V from the outlet and convert it to a DC voltage such as 12V or 48V, depending on converter type. An incorrect converter will provide the wrong voltage which may damage the fan e.g. AC/DC 24V converter on a 5V fan.


How to Calculate Electricity Costs

             Ever wondered how much it would cost to run your fan continiously for a certain period of time? Use this simple equation to find out. The fans wattage (W) is located on the specifications tab or spec sheet for each fan. You may also want to look at your electricity bill to find out how much you are being charged per kWh.

wattage x hours used ÷ 1000 x price per kWh = cost of electricity


Let’s take a look at the standard high speed 120 by 38 mm AC fan. According to the manufacturers spec sheet, it has wattage rating of 18 W. Let’s assume that you are being charged $0.14 per kWh, the average rate in the US. We take 18, multiply by 24, divide by 1000, and multiply by 0.14, to get a rate of $0.06 per 24 hour day. Multiply that by 30, and we're looking at a cost of around $1.80 per month to power this fan model continuously.