FIND A DEALER OR DISTRIBUTOR
Back at the 1983 Chicago World’s Fair, the Fair’s Director of Works, Daniel Burnham, had an important decision to make about the power supply for a building dedicated entirely to electrical exhibits at the fair. General Electric, with Thomas Edison’s and J.P. Morgan’s support, proposed a package using direct current (DC), which Burnham deemed too expensive. That was when Westinghouse submitted a much lower bid using Nikola Tesla’s alternating current system (AC). Burnham chose Westinghouse, and alternating current, or AC, became the standard power supply for the United States. However, some equipment, including camera equipment, prefers a direct current (DC) to charge up batteries or even to power the camera directly. This is where AC adaptors come in handy.
AC adaptors are like a power cable a power transformer built into the line. When you plug an AC adaptor into a wall, it will transform the alternating power current into small chunks of energy that are better utilized by the appliance in question, whether it be a cell phone, laptop, camera battery, or other device. These adaptors make it possible to transform a simple alternating current into usable energy for a variety of applications, make AC both versatile and efficient.
In the professional video industry the preferred AC adaptor of choice is one that you can use for both charging batteries and providing power to your video camera directly, especially if you bought both the batteries and the cameras as part of a universal camera kit. The kit usually comes with an AC adaptor that is also a single, double, or quad charger. For times when an operator is in a fixed location shooting, using the AC adaptor’s 4-pin XLR connection to power up is optimal. This saves battery power and ensures constant power to the camera.
Camera operators in particular will want to review the total power requirements of their camera system and use an AC adaptor that has adequate headroom to power the device. For example, a camera requiring 35Wh of power could use an AC adaptor/power supply that features 60Wh. Some AC Adaptors also act as a Power Base – they can “auto-sense” when AC power has been disconnected or failed; charged batteries in place on the adaptor then feed power out to a device from the 4-pin XLR connectors.
