PLC Programming Languages: The term PLC programming languages refers to the method by which the user communicates information to the PLC. The two most common language strucÂtures are ladder diagram…
AC Input: The, ac input modules that are commonly available work with 24, 48, 110 and 220 V. It is important to use the one that fits the needs based…
Timer: Timer is an instruction that waits a set amount of time before doing something. The different kinds of timers are available with different manufacturers. Most of the timers are:…
PLC System Operation: A PLC System Operation works by continually scanning a program. This scan cycle can be considered as made up of three important states as shown in Fig.…
PLC Structure: The PLC Structure mainly consists of a CPU, memory areas, and appropriate circuits to receive input/output data as shown in Fig. 21.22. A PLC can be considered as…
Cascade Control with Digital Controllers: A simplified system to control the temperature of a process employing a gas burner using two Cascade Control digital controllers is shown in Fig. 21.21.…
Direct Digital Control: Developments in digital electronics have led to many industrial processes being computer controlled. The first system used was Direct Digital Control (DDC), in which a computer measured…
Basic Automatic Control: Multivariable systems are used more commonly in this age of Basic Automatic Control. Control parameters are becoming more complex by the day and the range of applications…