FIELD: electrical engineering.
SUBSTANCE: invention relates to electrical engineering, namely to a device for diagnosing solenoid valves. The solenoid valve 1 consists of an electromagnet 10 and a valve body 12 in which one or more holes are made. The electromagnet 10 contains a solenoid 102, in which there is a movable core 104 made of ferromagnetic material. The flow of fluid, for example compressed air, supplied through the opening of the solenoid valve, is blocked or passed by the movable core 104 when the power supply to the solenoid is supplied or disconnected. When power is supplied to the solenoid 102, the movable core 104 opens the opening of the normally closed (NC) valve or closes the opening of the normally open (NO) valve. When the power supply to the solenoid is turned off, the spring 106 returns the core to its original position. The method for diagnosing solenoid valves contains the following steps: a) determining when the solenoid is excited, the rate of change in time (dV/dt) of the solenoid supply voltage and comparing it with a preset value; b) if the specified rate of change is less than the specified preset value, an error signal is generated, otherwise c) determining the characteristics of the shape of the solenoid current curve in time between the moment of excitation of the solenoid and the moment when the movable core reaches the position of the end of its stroke; d) comparing the characteristics of the detected curve shape with predefined threshold values; e) if the detected characteristics are less than the specified predefined threshold values, an alarm is generated, otherwise, f) when the solenoid current is in a stable state, the value of solenoid resistance (R) is calculated and compared with the predefined minimum resistance value (R0) and with the predefined maximum resistance value (R1); g) if the resistance value of the solenoid (R) is less than the preset minimum resistance value (R0) or greater than the preset maximum resistance value (R1), an alarm signal is generated.
EFFECT: monitoring the operation of solenoid valves to detect possible malfunctions or significantly decrease the values of their operational characteristics.
18 cl, 10 dwg
