In electrical equipment, SF6 gas is a common insulating medium, while SF6 relay and pressure gauges play an important role in monitoring and protection. This article will discuss in depth the differences between SF6 relays and pressure gauges, as well as their specific functions in electrical systems.
Pressure gauges are used for monitoring, that is, detecting the pressure of the system. SF6 relays not only monitor the changes in system pressure, but also provide control and protection. SF6 relays can be set to open and close signal contacts at different pressure states. Usually, there are alarm contacts and self-locking contacts, while pressure gauges do not have contacts, which is the difference between them. SF6 relays are pressure relays with temperature compensation, mainly used to send alarm signals and lock signals. Gas pressure gauges are installed on circuit breakers to monitor the pressure changes of SF6 gas in electrical equipment. Density meters monitor gas leakage in electrical equipment. The main function of SF6 relays is to monitor the density of SF6 gas in circuit breakers. Density is actually a pressure monitoring with temperature compensation.
In a sealed container, the pressure of SF6 gas at a certain temperature can represent the density of SF6 gas. It is customary to use the pressure of SF6 gas at 20°C as the standard value. During on-site calibration, the measured pressure value should be converted to the corresponding pressure value at different ambient temperatures at 20°C to determine the performance of SF6 relays. SF6 relays play a control and protection role in the monitoring of electrical equipment.