High-voltage/high-current circuits in antenna, radar, rangefinder, satellite, military ground vehicles, shipboard, and other aerospace and defense applications — as well as 270-VDC aircraft power systems — pose unique power-management challenges. Today, it’s critical to design solutions that can handle high power more efficiently in less space. Power distribution for electric vehicles, charging stations, battery systems, and solar and wind applications pose similar challenges.
This discussion simplifies a designer’s task by describing how advanced relays and contactors can handle difficult power-distribution demands — and introduces a tool for navigating various contactor and relay features to facilitate selection.
Power-distribution technology comes in a variety of flavors. Many open-air switch designs can handle only several hundred volts. However, smaller, lightweight, hermetically sealed devices using either a gas with good dielectric properties or a vacuum can switch up to 70 kilovolts (kV).
For contactors, increased contact size and pressure, combined with special alloy materials, enable high current management up to 1,000 A. Integrating built-in Hall-effect current sensors into the contactor creates “smart” current-sensing versions of these devices.