PM891/PM891k01 ABB PM891/PM891k01

PM891

The PM891 processor is a monolithic unit equipped with a power supply, CPU board, and unit terminal. The unit contains a microprocessor and RAM memory, a real-time clock, LED indicators, INIT buttons, and a secure digital interface. The PM891 does not contain any internal battery. The PM891 has two RJ45 Ethernet ports (CN1, CN2) for connecting to the control network and an RJ45 serial port (COM4). The COM4 port is isolated and used by the configuration tool. The PM891 supports CPU redundancy for higher availability (CPU, CEX bus, communication interface, and S800 I/O). The Communication Expansion bus (CEX bus) is mounted on the device. The CEX bus is used to extend the on-board communication port with a communication interface unit. Redundant communication interfaces can be used on the CEX bus. The CEX bus interconnect unit BC810 is used to improve the usability of the CEX bus by dividing it into separate segments. The device’s optical module bus can be used to connect seven groups of S800 I/O devices (each group contains up to 12 devices). Each PM891 has a unique Ethernet address that provides hardware identification for the device.

Processor is the Central Processing Unit (CPU), also known as the Central Processing Unit (CPU). Its main function is to carry out operation and logic operation. Its internal structure can be divided into several parts, such as control Unit, arithmetic logic Unit and memory Unit. According to the word length of its processing information can be divided into: 8-bit microprocessor, 16-bit microprocessor, thirty-two microprocessor and sixty-four microprocessor and so on