Sulfur hexafluoride gas recovery rate measuring device and method

The invention provides a device and a method for measuring the recovery rate of sulfur hexafluoride gas. The device comprises a sulfur hexafluoride gas recovery device body, a PLC (Programmable Logic Controller), a three-way pipe joint, a constant-volume gas storage tank, a temperature sensor and a gravity sensor, the electrical equipment gas chamber, the constant-volume gas storage tank and the sulfur hexafluoride gas recovery body are correspondingly connected with connectors of the three-way pipe connector through pipelines respectively, a first electromagnetic valve and a second electromagnetic valve are arranged on a pipeline of the constant-volume gas storage tank, and a third electromagnetic valve is arranged on a pipeline of the sulfur hexafluoride gas recovery body. A pressure sensor and a temperature sensor are arranged between the first electromagnetic valve and the second electromagnetic valve, a gravity sensor is arranged at the lower end of the gas storage device of the sulfur hexafluoride recov