Transformation method for gas density relay, and gas density relay having online self-check function and check method thereof

A gas density relay with online self-check function, comprising a gas density relay body, a gas density sensor, a pressure regulating mechanism, a valve, an online check contact signal sampling unit, and an intelligent control unit;

• wherein a gas path of the pressure regulating mechanism is connected with the gas density relay body, the pressure regulating mechanism being configured to enable a contact signal action of the gas density relay body in response to pressure rise and fall of the gas density relay body;
• wherein the gas density detection sensor is communicated with the gas density relay body;
• wherein the online check contact signal sampling unit is connected with the gas density relay body and configured to sample contact signals of the gas density relay body under the ambient temperature;
• wherein one end of the valve is provided with an interface connected with the electrical equipment, and wherein the other end of the valve is connected with the gas density relay body or with the gas path of the pressure regulating mechanism to connect the valve with the gas density relay body;
• wherein the intelligent control unit is connected with the gas density sensor, the pressure regulating mechanism, the valve, and the online check contact signal sampling unit, wherein the intelligent control unit is configured to manage the closing or opening of the valve, to control the pressure regulating mechanism, to collect pressure values, temperature values or gas density values, and to detect the contact signal operating value or contact signal return value of the gas density relay body;
• and
• wherein the contact signals include one of alarm signals and blocking signals.