This series of reactive power compensation measurement and control devices is a new generation product developed and produced by our company to meet the needs of low-voltage reactive power compensation development, which is used in conjunction with our composite switch products. This product adopts a universal instrument size for easy installation and use. The human-machine communication uses LCD display and buttons, and has capacitor status indication. Controlling the physical quantity to reactive power solves the switching oscillation of capacitors. Adopting dedicated measuring chips for high-precision measurement of various electrical energy parameters, with high control accuracy. Equipped with overvoltage, undervoltage, over temperature and other protection functions, when the power grid parameters exceed the set limits, the controller quickly cuts off the capacitors that have been put into operation, protecting the safe operation of the capacitors and extending their service life.