Precise Industrial Timer Project
Industrial timers are widely used in the industry for the automatic control of electrical appliances. Most of the timers available on the market are either of complicated quality or of poor quality with an unsatisfactory cost / performance ratio. This industrial panel mount timer provides excellent time accuracy for industrial use. The 7-segment display for displaying the account is directly controlled by the microcontroller (MCU) without integrated control circuits. Circuit and operation The circuit diagram of the industrial timer is shown in Figure 1. It is built around the 5V 7805 voltage regulator (IC1), the AT89C52 MCU (IC2), the 5V relay (RL1), two thumbwheel switches (TWS1 and TWS2) and discrete switches. Components. Circuit diagram of the industrial timer Fig. 1: Diagram of connection of the industrial timer The circuit is powered by a 230V AC network. The transformer (X1) reduces the voltage from 230V to 7.5V-0-7.5V. The diodes D1 and D2 are rectifying diodes and the capacitor...