Today’s science tip: A detailed explanation of the working principles of ABB!

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Everyone has been usingABB positioners for such a long time – has anyone ever understood the functional principles of these positioners? Many people are aware of its performance characteristics and simple working principle, but they do not have a thorough and in-depth understanding of its functional mechanism. Next, the editor will introduce this section to you in detail. 　　The ABB positioner has a separate wiring box and a robust aluminum enclosure, with separate modules underneath. The rotary actuator is equipped with a cam with a 100° angle. Scanning is carried out using an inductive contactless sensor, and the angle of rotation is then converted into an electrical signal. This causes the movement of the actuator to drive the rotation axis of the positioner. The position sensor, CPU, and cam form an adjustment unit that can only be replaced by the manufacturer; the position sensor includes a temperature sensor for measuring the temperature inside the chamber, while the cam does not need to be replaced by the user. ​　　The pneumatic output module of the ABB positioner consists of an analog 3-position 3-way valve acting as the main stage and a pilot stage. The pilot stage converts electrical signals into pressure signals. This process is carried out by a system consisting of a nozzle flap and a coil magnet. The pressure control main stage has an intermediate position in addition to the two exhaust and intake positions. After reaching the set point, to prevent air loss at the main stage, the valve switches to the intermediate position. For a double-acting output, there can be two main stages. The microprocessor calculates the control error and outputs the corresponding correction signal to the pneumatic unit. The electrical unit reads the setpoint of the 4–20mA input circuit, and then the process variable is controlled by a position sensor whose value is converted by an A/D converter. 　　The above provides a detailed explanation of the functional principles of the ABB positioner. Those who still do not understand this topic can watch our related content; we hope it will be helpful to you.