Honeywell 621-4550 Digital Input Module

Honeywell 621-4550 Digital Input Module

Brand: Honeywell

Module: 621-4550

Description: Digital Input Module

Product Orgin: USA

Introduce for Honeywell DCS
1. TDC2000 produced many important achievements in the field of control system at that time, such as redundant controller, redundant control network (DH-Data Hiway), human-machine interface and so on.
According to the principle of distribution, the basic function distribution characteristics of the whole TDC2000 are as follows: the control network adopts single-layer redundancy structure; The operation station is responsible for operation and data storage; Different controllers implement different process control and so on. This basic function distribution is still used by some control manufacturers of DCS.

2. As the most typical DCS system, TDC3000 further embodies the concept of distributed control, with the following main characteristics:
To meet the needs of large-scale production, the two-layer control network architecture, each LCN can connect 10 UCNs, each UCN can connect 32 pairs of redundant controllers. 64 LCNs can also be linked by NG.
Three-layer control platform
1) PMX realizes the most basic loop regulation, logical linkage, sequence control and complex loop control.
2) AM to achieve advanced control
3) Optimized control by VAX
The introduction of emergency shutdown system SM, to achieve safety production protection.
TDC3000 is one of the most classic DCS systems, to meet the large-scale safety production, complex control and advanced control applications. It is widely used in industrial production control, especially in many large-scale petrochemical combined production plants.

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