ABB S-093H 3BHB009885R0004 Phase Module High Voltage Variable Frequency Frame

Description

DCS systems usually use several controllers (process stations) to control numerous control points in a production process, and each controller is connected through a network and can exchange data. The operation adopts a computer operation station, which is connected to the controller through a network to collect production data and convey operation instructions. Structurally, DCS includes process level, operation level, and management level. The process level is mainly composed of process control stations, I/O units, and on-site instruments, and is the main implementation part of system control functions. The operation level includes: operator station and engineer station, completing system operation and configuration.

When grounding the DCS control system on site, it is necessary to strictly follow the grounding specifications of the DCS manufacturer, otherwise it will affect the reliability of the DCS system. When grounding the DCS system on-site, the following points should be noted:
(1) The power ground of the I/O cabinet and the power ground of the UPS must be connected to the same ground to ensure equal potential.
(2) The grounding cable must meet the requirements of the DCS manufacturer and be connected to a dedicated grounding screw inside the cabinet.
(3) The system grounding and shielding grounding cannot be combined in the cabinet and must be separately connected to the grounding grid.
(4) Cabinet grounding cannot be replaced by cabinet parallel bolts, and must be strictly connected with grounding wires.
(5) The grounding should be firm and reliable, and the busbar connection plate should be coated with anti-corrosion paint.
(6) The grounding resistance meets the requirements of the DCS system and must be strictly measured.

From the hierarchical structure of the DCS control system, it can be divided into three major parts: controllers with I/O components, communication networks, and human-machine interfaces (HSIs). The controller I/O components are directly connected to the production process and receive signals from on-site equipment; The human-machine interface is a device for exchanging information between operators and DCS; The communication network connects the controller and human-machine interface to form an organic whole. The communication networks of early DCS systems were dedicated, with several levels of network to complete communication between different modules. From the current situation, there are four maximum network levels for DCS, namely I/O bus, field bus, control bus, and DCS network.

I/O bus, which sends various I/O signals to the controller, which reads the I/O signals. This is called the I/O bus. I/O boards do not exchange data with each other. The speed of the I/O bus is not high. From tens of K to a few megabytes. This is related to the development of computer technology. In the early 1980s, it was 20K, in the mid 1980s it was 40K, in the late 1980s it was 80K, and in the 1990s it was a few megabytes. For speed, it is best to use a parallel bus. Adopting a parallel bus, the I/O module must be adjacent to the controller module. In the case of using a serial bus, the distance between the I/O board and the controller should also be relatively close. It is best to install the controller module and I/O module in one cabinet or adjacent cabinets. Remote I/O should use fieldbus. Such as CAN, LONWORKS, HART bus, etc. Fieldbus was developed in the early 1990s.

In terms of hardware, there should be input and output boards in the I/O board that can receive signals from the fieldbus. From a software perspective, there should be functional blocks in the controller for reading and writing fieldbus signals. In DCS systems, remote I/O uses a more common HART bus. For example, for on-site transmitters that are relatively far from the controller cabinet, the signals from 16 transmitters are grouped together and sent to the controller using a HART bus. The controller reads the signals from the 16 transmitters simultaneously. The distance between the controller and the transmitter can be more than 1 kilometer. Almost all DCS systems imported from the United States and Europe have a HART protocol board. In practical applications, remote signals are quite common. For example, in cement factories, the distance between the kiln head and kiln tail of rotary kilns is several hundred meters. If two nodes are set up on the network, two sets of interface modules are required, and the cost of interface modules is relatively high. If one node is set up, remote I/O is required regardless of whether the nodes are arranged at the kiln head or kiln tail in geographical location.

DSIH 72VP ENOK
DSIH 72VP ENOK
DSIH 72VP ENOK
DSI020
DSG71-S
DSG71-M45
DSG71-M ID40100
DSG71-M ID23508
DSG71-B
DSG56-S ID40381
DSG56-S ID34713
DSG56-S ID23507
DSG56-S
DSG-56-M-3-5
DSG56M25
DSG56-L ID23506
DSG56-L
DSG45-S ID23505
DSG45-M ID39713
DSG45-M ID27905
DSG45-M
DSG45-L ID59528
DSG45-L ID14814
DSG45-L 922 11929
DSG45-L 20511667
DSG 71-S45-UL
DSG 71-S
DSG 71-M
DSG 71-K
DSG 71-C
DSG 56-S
DSG 56-M
DSG 56-L
DSG 56 M25
DSG 45-M
DSG 45-L
DSG 100-S
DSF 132 M-54W20-5 UL
DSE-IBSC33-1.40
DSE-IBS 3.02
DSE-IBS 3.02
DSDXB001
DSDX453