
Closed Loop Motor Control Closed loop (servo) control is used to make a constant speed motor control. Constant speed means that the speed of the motor will be kept constant although the load is change, or even when the electric supply voltage is also changed. The circuit maintain the speed at a constant value [...]
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Controlling the speed of three phase ac motor is done by controlling the frequency of the power line supply, since the motor is synchronized with the line frequency. Three phase ac motor speed controller is actually nothing more than three phase sine wave power inverter with variable frequency. The three phase power inverter is a [...]
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A phase control circuit can be used to control the power delivered to an AC load. The phase control circuit control the AC waveform, cutting the cycle to give full cycle, half cycle, zero cycle, or somewhere in between. You can say this circuit is similar to a dimmer circuit, but the switching is synchronized [...]
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Computer-controlled 4-20mA current loop is useful to control some industrial equipments. By current loop, transmitting the signal over long distant should be resistant from noise interference. This computer-controlled 4 – 20mA is designed to operate on a single supply over a range of 3.3V to 30V. The zero reference of 4 [...]
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Thermocouples give many benefits compared to thermistor/RTD (Resistance Temperature Devices). Some advantages of thermocouple are their wider temperature range, their reliability, and their consistency over long period of time. In some cases, thermocouple calibration is even unnecessary. Thermocouple temperature sensors are widely used in temperature controllers for boilers, oven, pressurized reactor, even in high temperature [...]
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RCV420 is a special function integrated circuit chip for 4-20mA current loop receiver. RCV420 provide complete 4-20mA to 0-5V conversion, with 0.1% overall accuracy, 86dB CMR, and ±40V common-mode input range. This IC chip is suitable for many applications: PROCESS CONTROL INDUSTRIAL CONTROL FACTORY AUTOMATION DATA ACQUISITION SCADA [...]
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