When a PLC is used primarily to replace relays, timers, and counters, it's hard to beat the simplicity and usefulness of ladder diagram programming. Their ability to accept programming in ladder ...

Fig. 2. Ladder logic uses memory locations rather than hard-wired logic. For the program shown in Fig. 2, we took the relay logic’s ladder diagram from Fig. 1 and duplicated it with ladder logic — no ...

THE use of function blocks for programming of programmable logic controllers (PLCs) is gaining wider acceptance. Rather than the classic “contact and coil” representation of ladder diagram or relay ...

There are few elements, e.g. the signal relay coil 5XJ1 and the contact 5XJ1, are not in the same path, their control relations can be achieved through adding member variables respectively. There are ...

The IEC 61131 standard is commonly used for the programming of Programmable Logic Controllers (PLCs). One of the graphical languages of this standard is the ladder logic diagram based on the circuit ...

In this paper, I focus on the scan processing method called cyclic scan as the execution method of PLC (Programmable Logic Controller) and introduce the discrete time based on such execution method. I ...