Gas density relay with online self-checking function, and checking method therefor

A gas density relay with the function of online self-check, comprising a gas density relay body, a first pressure sensor, a temperature sensor, a force measuring sensor, a driving contact action mechanism and a control unit;

• wherein
• the gas density relay body comprises a shell, a pressure detection element, a temperature compensation element, a signal generator and a signal action mechanism arranged in the shell;
• the first pressure sensor is connected to the pressure detection element of the gas density relay body;
• the driving contact action mechanism is arranged inside or outside the shell, and includes a force application mechanism and a motion mechanism, the force application mechanism includes a driving component and a force transmission component driven by the driving component, the motion mechanism includes a push rod, which moves under the drive of the force application mechanism, directly or indirectly displaces the signal action mechanism to trigger the signal generator to generate contact signal action;
• the force measuring sensor, which is arranged on the driving contact action mechanism or in the shell, is configured to detect the force exerted by the driving contact action mechanism on the gas density relay body;
• the control unit is respectively connected to the driving contact action mechanism, the first pressure sensor, the temperature sensor and the force measuring sensor, and is configured to control the driving contact action mechanism, to acquire pressure values, temperature values, and gas density values, and to detect the contact signal action value and/or contact signal return value of the gas density relay body;
• wherein, the contact signals include alarm signals or blocking signals.