Valve electric device overload fault handling
Valve electric actuator is used for valve operation and one of the devices connected to valve. The device is driven by electricity, its movement process can by travel, torque, or to control the size of the axial thrust. Valve electric device depends on the working characteristic and utilization of the valve type, installation work ethic and the position of the valve in the pipeline or equipment. Choose based on: 1. Operating thrust. There are two kinds of valve electric device of the host structure, one kind is not configuration thrust plate; The other is a configuration have thrust plate. 2. Operating torque. Operating torque is to select the main parameter of valve electric actuator. 3. Stem diameter. If electric device allows the largest stem diameter can't through the stem of the valve, cannot assemble into electric valve. Valve electric device adopts usually limiting torque shafts. When the specifications of the electric actuator was determined, the control torque is also determined. When its in a predetermined time, motor generally do not overload. Low voltage power supply and can not get the required torque, the motor stop running. Setting a torque limit institutions, wrongly, that makes it more than stop torque, excessive torque caused by the continuous, make the motor stop running. As at intermittent use, the heat generated by the savings, more than the permissible temperature rise of the motor. A torque limit institutions circuit for some reason fails, the torque is too big. Using the environment temperature is too high, relative to bring down the heat capacity of the motor. GT pneumatic rubber fluorine pneumatic explosion-proof flanged ball valves flanged ball valves GT GT GT pneumatic fast loading butterfly valve therefore must adopt the mode of combination of various methods. But because the load of every electric device is different, it is difficult to put forward a unified way. But for the most part, also can find common ground. Increase or decrease of the motor input current judgment; In the judgement of motor itself fever. The above two ways, both the heat capacity of the given time allowance to consider motor. If a single way to that of the heat capacity characteristics of the motor is difficult. So should choose according to the cause of the overload can reliable method of action - — Combined composite method, in order to realize the comprehensive overload protection. Continuous operation of motor or point operation overload protection by using a thermostat; Use fuse or overcurrent relay for short circuit accident. Correct selection of the valve electric actuator and is alawys related to prevent overload, should be taken into consideration seriously.