FIELD OF THE INVENTION
The present invention relates to a HMI (Human Machine Interface) based control system for
integrating the hydraulic down coiler for the Hot Strip Mill (HSM) Automation system in steel
plants and integrating with rest of the mill, in a user friendly reliable manner enabling data
input for desired process parameters and interfacing of operator through a HMI system to
the computer based control system. The system of control of the invention is adapted to
exist in tandem with the conventional COROS HMI operating on Master-Slave mode by a
parallel system in an economic manner such that all the raw data received in Operator
Interface facilitate achieving reliable operation of the system free of any complexities of
maintenance or longer down-time for scarcity/obsolescence of spares and with the provision
for future expansion/improvement of the system. Importantly, the system of the invention
involves selective data visualization software for better and improved user friendly HMI
(Human Machine Interface) based control. The present invention thus provides for a
customized control provision and also provides means for centralized monitoring of all
automation equipments/systems integrated in network, resulting in improved quality and
productivity of HSM.
BACKGROUND ART
It is well known in the art of process automation in continuous processing plants including
sections of steel plants, that the computer with real time operating systems are extensively
used in automation of industries where mathematical calculations of control parameters with
fast response is required. Each of such computers in a distributed computer system is
usually dedicated to perform a particular function. It is essential to have a Human-Machine-
Interface (HMI) system for executing control through the computer system that is adapted
to provide real-time display of process parameters with facility for operator's data input of
process variables and control. The HMI thus acts customarily as virtual computer facilitating
the operator with ease of operation and control insulating from the underlying complex
control system.
Hydraulic Down coiler in Hot Strip Mill (HSM) in RSP, SAIL, is conventionally controlled by
the existing MMC-216 (Siemens make) computer system with a proprietary OS BD-216.
This system consists of a total 16 numbers of micro computers with 8086 processors
arranged in an hierarchical manner is exchanging data among them through shared
memory and parallel bus system. In the first level there are four processors arranged in a
2

rack with common backplane bus. One of the processor acts as a router to couple to the 2
systems in the next level, where there are two identical systems each with three processors.
Two of the processors have slave processors for PID control of the hydraulic valves of the
down coiler system of HSM. Thus the existing system have nine processors exchanging data
among themselves viz.- three numbers in first level, three numbers in second level system-
I and three numbers in second level system-II.
The 8086 processors used in the existing control system have segmented memory
management. Out of the 16 segments, one segment (segment C) is connected such that it
is common among all processors in the same rack. The segment of lower rack is mapped to
one of the segments of the higher level rack. Thus data exchange between all the nine
processors take place through the router processor. The processor for the HMI, termed as
the VE02, has a communication processor (CP) which is having a dual port RAM, through
which data exchange is taking place between VE02 and CP. The data communication
between the CP and HMI is serial communication using RS 232 C protocol.
The VE02 requests data from all other processors at fixed intervals, and all processors
respond by sending a telegram package. The data is processed and split into different
packets depending on the time criticality of the and send CP through the dual-port RAM.
Interpretation of the data by CP to HMI is performed exclusively by the HMI itself i.e. the
COROS-LSB HMI system developed in iRMX OS based on 80286 processors.
There are three stations for the HMI. There is master station with Hard Disk, which contain
all masks and configuration data. There are two numbers of slave systems also which do not
have any hard disks. The configuration data and the mimics for a selected screen are
retrieved from the Master station. The coordination between the Master and the slave
stations is performed by the Communication Processor (CP). For the existing system, the
only input device was the keyboard. For ease of menu selection and data entry by the
operator, a programmable keyboard with 128 keys was provided and whenever any key is
actuated/pressed, a scan code is sent to the serial communication port of HMI station and
the HMI software interprets the data and sends the code to CP.
Thus in the existing system one processor out of 16 processors, is dedicated for HMI
functions, which collect data from all other processors, process them and then send them to
3

Siemens make COROS-LSB HMI system. The data entry being executed through a 128 key
keybord. The COROS system operating on iRMX OS, based on 80286 processors operates on
master-slave mode to display the data on master terminal and two numbers of slave
terminals having EGA grade monitors. Data input from COROS system is processed and
distributed to all the relevant processors for controlling system variables/parameters in
down coiling. The processor in MMC is interfaced to COROS system through a
communication card, which has a dual-port RAM accessible by processor at MMC end and
the communication processor itself.
With the advent of advanced automation and control systems for industrial processes the
COROS HMI system became obsolete and unreliable for Hydraulic down coiler system for
Hot Strip Mill Automation in steel plants. The replacement and routine maintenance of such
a system was difficult and time consuming due to obsolescence of vital spares and
components, leading to longer down time and lower productivity.
There had been therefore a persistent need to develop an advanced control system with
HMI interface for the Hydraulic down coiler of the Hot Strip Mill to avoid the above stated
disadvantages and limitations of the existing system, with provision of simple and easier
operation and maintenance with higher reliability. Moreover, the need for integrating the
coiler automation system with rest of the Mill is also found desired in the art. More,
importantly the deficiency in the existing MMC system is further found to reside in not
supporting any fast communication protocols because of involvement of serial
communication protocols and slowing down of the speed of processing and there is thus
need to make MMC systems faster and more effective and reliable for the desired
operational control in HSM.
OBJECTS OF THE INVENTION:
It is thus the basic object of the present invention to provide an effective alternative to the
HMI system with a new system of computer based control for control of Hydraulic down
coiler of Hot Strip Mill to facilitate desired improvement upon the functionality of the
obsolete COROS system and meet the need of the art.
A further object of the present invention is directed to eliminate the problems associated
with the obsolescence of the existing COROS system without sacrificing the functionality of
4

the existing HMI system such that the improved system is more transparent to the
maintenance personnel for trouble-shooting, readily available spares and ease of repairing
and thus minimizing the down-time of equipments and associated costs, leading to higher
productivity.
A further object of the present invention is directed to achieving a new HMI based
automation system for control of hydraulic down coiler of Hot Strip Mill having flexibility in
its features to facilitate future expansion and system up-gradation.
A still further object of the new HMI system is to help in data exchange with automation
systems in other areas and provide for better operators' guidance.
A still further object of the system of the present invention is to make it capable of trending
of important process parameters and ready information about the status of important
equipments available to the operations managers, that would help analyzing the
performance of control elements and improved means for centralized monitoring of
managerial/technical decision process resulting in improved quality and productivity of HSM.
A still further object of the present invention is directed to integrate the coiler automation
system with other subsystems in rest of the Mill.
Another important object of the present invention is directed to provide for a HMI interfaced
computer control system for hydraulic down coiler in HSM, to achieve faster speed of
processing data/information communication for efficient control involving selective means
of interfacing the MMC to a PLC by memory sharing and windows based HMI to
communicate with the PLC activated with requisite customized software developed for the
purpose.
SUMMARY OF THE INVENTION
Thus according to the basic aspect of the present invention there is provided a Human
machine interface(HMI) system for control of Hydraulic Down coiler of hot strip mill
comprising:
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processor means for the human machine interface adapted to receive raw data and
forward through communication to processor for communication with other
computers;
said processor for communication with other computers interfaced with respect to a
PLC via an interface card adapted to work as an intelligent peripheral of said PLC and
communicate with the processor of MMC through memory sharing;
communications processor means installed in said PLC adapted to connect the HMI
on PROFIBUS and further communicate data to other PLC over the PROFIBUS
network; and
WinCC based operator data input and visualization means.
A further aspect of the present invention is directed to said Human machine interface
system wherein said interface card comprises a S5 Bus Coupler which is adapted to work as
an intelligent peripheral of said PLC and communicate with the processor of MMC through
memory sharing.
A still further aspect of Human machine interface system for control of Hydraulic Down
coiler of hot strip mill comprising:
Common function processors including (i) processor adapted as router to systems for
coilers;(ii) processor adapted as operator interface;(iii)Communication Processor for
HMI (iv) common equipment control processor and (v) processor for communications
with other systems;
said communication processor for HMI operatively connected to a COROS master
system and two numbers of COROS slave systems;
6

said processor means for communicating with other systems operatively connected
to a cooperative PLC with bus coupling with MMC computer, having a profibus
communication processor ;and
said profibus communications processor operatively connected to other PLC/HMI and
Win CC based operator data input and visualization means.
According to a further aspect of the Human machine interface system of the present
invention wherein said processor for communication with other computers is adapted such
that on receipt of input data through said interface card the same is analysed and sent to
the processor for HMI, said processor for HMI adapted to put the data in buffer received
from its communication processor (for COROS).
A still further aspect of the present invention directed to a Human machine interface system
wherein said COROS HMI is provided with programmable 128 key keyboard for input of
operator data and command.
According to yet another aspect of the present invention directed to said Human machine
interface system comprising means to interface the serial keyboard to Win CC system
through COM technology involving driver software.
Said Human machine interface system of the present invention wherein said driver software
comprise Visual Basic/Visual C++ based driver software.
The present invention and its advantages and objectives are further described in greater
details with reference to the accompanying non-limiting illustrative figures.
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BRIEF DESCRIPTION OF THE ACCOMPANYING FIGURES
Figure 1: is an illustration of the presently available arrangement for desired control
of Hydraulic down coiler system in Hot Strip Mill; and
Figure 2: is an illustration of the modified arrangement in accordance with the
present invention for desired control of Hydraulic down coiler system in Hot Strip
Mill.
DETAILED DESCRIPTION WITH REFERENCE TO THE ACCOMPANYING FIGURES:
The present invention relates to an improved system for HMI based control for Hydraulic
Down Coiler of Hot Strip Mill in steel plants. It is known in the art that Hydraulic Down coiler
in Hot Strip Mill (HSM) is conventionally controlled by the existing MMC-216 (Siemens
make) computer system with a proprietary OS BD-216. This system consisting of a total 16
numbers of micro computers with 8086 processors arranged in an hierarchical manner is
exchanging data among them through shared memory and parallel bus system. In the first
level there are four processors arranged in a rack with common backplane bus. One of the
processor acts as a router to couple to the 2 systems in the next level, where there are two
identical systems each with three processors. Two of the processors have slave processors
for PID control of the hydraulic valves of the down coiler system of HSM. Thus the existing
system have nine processors exchanging data among themselves viz.- three numbers in
first level, three numbers in second level system-I and three numbers in second level
system-II.
As the MMC system does not support fast communication protocols but slow down the
system by using serial communication protocols and is also not able to effectively integrate
the coiler automation system with rest of the mill, the present invention is directed to
achieve faster and efficient control through selective disposition of preferred hardware and
software means to improve upon the ease of operator interface with HMI, in a cost
optimized way. The existing MMC is interfaced with a S5-115U PLC by memory sharing
technique and using Windows based compatible HMI system available off-the-shelf , to
communicate with the PLC. The required software was developed for both MMC and PLC for
favoured interfacing the HMI. The present invention thus eliminated the down time for the
control system due to product/spares obsolescence.
8

Reference is first invited to accompanying Figure 1 wherein the existing conventional mode
of operation of the COROS HMI interfaced with the MMC-216 computer system operating on
BD-216 OS for control of the hydraulic down coiler system in the Hot strip Mill has been
illustrated. It can be noted in Figure 1, that this system consisting of a total 16 numbers of
micro computers with 8086 processors arranged in an hierarchical manner is exchanging
data among them through shared memory and parallel bus system. In the first level there
are four processors arranged in a rack with common backplane bus. One of the processor
acts as a router to couple to the 2 systems in the next level, where there are two identical
systems each with three processors. Two of the processors have slave processors for PID
control of the hydraulic valves of the down coiler system of HSM. Thus the existing system
have nine processors exchanging data among themselves viz.- three numbers in first level,
three numbers in second level system-I and three numbers in second level system-II.
The 8086 processors used in the existing control system have segmented memory
management. Out of the 16 segments, one segment (segment C) is connected such that it
is common among all processors in the same rack. The segment of lower rack is mapped to
one of the segments of the higher level rack. Thus data exchange between all the nine
processors take place through the router processor. The processor for the HMI, termed as
the VE02, has a communication processor (CP) which is having a dual port RAM, through
which data exchange is taking place between VE02 and CP. The data communication
between the CP and HMI is serial communication using RS232 C protocol.
The VE02 requests data from all other processors at fixed intervals, and all processors
respond by sending a telegram package. The data is processed and split into different
packets depending on the time criticality of the execution requirement and send to CP
through the dual-port RAM. Interpretation of the data sent by CP to HMI is performed
exclusively by the HMI itself i.e. the COROS-LSB HMI system developed in iRMX OS based
on 80286 processors.
There are three stations for the HMI. There is master station with Hard Disk, which contain
all masks and configuration data. There are two numbers of slave systems also which do not
have any hard disks. The configuration data and the mimics for a selected screen are
retrieved from the Master station. The coordination between the Master and the slave
stations is performed by the Communication Processor (CP). For the existing system, the
only input device was the keyboard .For ease of menu selection and data entry by the
9

operator, a programmable keyboard with 128 keys is provided and whenever any key is
actuated/pressed, a scan code is sent to the serial communication port of HMI station and
the HMI software interprets the data and sends the code to CP.
Thus in the existing system one processor out of 16 processors, is dedicated for HMI
functions, which collects data from all other processors, process them and then send them
to Siemens make COROS-LSB HMI system. The data entry being executed through a
programmable keyboard . The COROS system operating on iRMX OS, based on 80286
processors operates on master-slave mode to display the data on master terminal and two
numbers of slave terminals having EGA grade monitors. Data from COROS system is
processed and distributed to all the relevant processors for controlling system
variables/parameters in down coiling. The processor in MMC is interfaced to COROS system
through a communication card, which has a dual-port RAM accessible by processor at MMC
end and the communication processor itself.
Reference is now invited to the accompanying Figure 2 wherein the desired faster and
efficient control means and manner of implementation of the hydraulic down coiler control
system of the present invention has been illustrated. It is to note that to facilitate achieving
said desired objectives, the new system has been developed to operate parallel to the
existing system for economy in investment on accessories and hardwares. All the data
received in VE02 are sent through communication to the processor for communication with
other computers (VE04). This processor is interfaced with S5-115U PLC through an interface
card for this purpose. This interface card (S5 bus coupler) works as an intelligent peripheral
of S5-115U PLC and communicates with the processor of MMC(VE 04) through memory
sharing. All the data received in VE04 was sent to S5-115U PLC. Required Communication
processor was installed in S5-115U PLC to operatively connect the HMI on PROFIBUS. The
data was sent to S7-400 PLC (Siemens make) over PROFIBUS network. The data
visualization software was configured in WinCC, and tested. The data input by operator in
WinCC was sent to S5-115U PLC, through S7-400 PLC and to VE04 through the interface
card. In VE04, the data was analyzed and sent to VE02. In VE02, this data was put in the
buffer received from CP (for COROS) and the system could be developed fully. The existing
COROS HMI had limited flexibility in respect of input of operator data and command entered
through a programmable keyboard with 128 keys. Moreover, the WinCC does not have
drivers for interfacing such a keyboard. Use of standard input devices like Mouse and
keyboard was found to be cumbersome for the operator. Hence necessary compatible
10

customized driver software was developed using standard programming languages like
visual basic/visual C++ for implementation of easier and user-friendly interface of the serial
Keyboard to WinCC system through COM technology.
The manner of implementation in an embodiment of the Windows based HMI for control of
hydraulic down coiler according to the present invention is further illustrated in
accompanying Figure 2, wherein five processors are placed in one rack in the level I and all
raw input data/command received in VE02 is sent to the processor VE04 for communication
with other computers in the system.
The VE04 processor is interfaced to the S5-115U PLC, in the level II, through its intelligent
peripheral S5 Bus coupler (S5-BUKO) adapted for communication with the processor of
MMC-216 computer system through memory sharing, such that all the data received in
VE04 is sent to S5-115U PLC. To connect the HMI on PROFIBUS, necessary communication
processor has been installed in S5-115U PLC, in level II, and the data is sent to Siemens
S7-400 PLC over PROFIBUS network. The data visualization software was configured in
WinCC and tested.
Currently available HMI based control systems are capable of communicating with
commonly used PLCs. Most of them use the standard communication protocols like
PROFIBUS, TCP/IP, DEVICENET and the like. Some of these have RS-232C serial interface
based protocols. However, no HMI package is known to be directly communicating with
MMC-216 system, as achieved in the present invention.
The Level three comprise a number of terminals for data input by operators through WinCC,
that are sent to S5-115U PLC through S7-400 PLC and also to other PLC based HMI systems
for Operative interconnections and integration with the MMC system. All such data are then
sent to VE04 in the next higher level through the interface card (S5 Bus coupler).
It is thus possible by way of the improved windows based HMI system for hydraulic down
coiler control in HSM of steel plants of the present invention, providing means for real time
control on process variables for better plant utilization and data exchange with automation
systems in other areas. The improved features of the windows based HMI for the control
system for hydraulic down coiler further provide means for trending of important process
parameters that help in analyzing the performance of control elements and simplify and
11

strengthen managerial decision process. Advantageously, the present system of HMI having
WinCC enabled interface with the MMC-216 processor helps in utilizing part of existing
facilities and thus achieving economy in installation costs. The use of the state-of-the art
hardware and software in the new HMI system interfacing with the mother MMC-216 system
helps not only in reducing threats of obsolescence of spares/components for the system but
also helps enhancing easier troubleshooting and integrating a network of plant-wide
subsystems for various control units. The present system is also capable of providing
information about the status of important equipment for achieving better control of the
operational parameters of the plant and a centralized monitoring of all automation
equipments , resulting in improved quality and productivity of HSM.
12

We Claim:
1. Human machine interface system for control of Hydraulic Down coiler of hot strip mill
comprising:
processor means for the human machine interface adapted to receive raw data and
forward through communication to processor for communication with other
computers;
said processor for communication with other computers interfaced with respect to a
PLC via an interface card adapted to work as an intelligent peripheral of said PLC and
communicate with the processor of MMC through memory sharing;
communications processor means installed in said PLC adapted to connect the HMI
on PROFIBUS and further communicate data to other PLC over the PROFIBUS
network; and
WinCC based operator data input and visualization means.
2. Human machine interface system as claimed in claim 1 wherein said interface card
comprises a S5 Bus Coupler which is adapted to work as an intelligent peripheral of
said PLC and communicate with the processor of MMC through memory sharing.
3. Human machine interface system for control of Hydraulic Down coiler of hot strip mill
comprising:
Common function processors including (i) processor adapted as router to systems for
coilers;(ii) processor adapted as operator interface;(iii)Communication Processor for
HMI (iv) common equipment control processor and (v) processor for communications
with other systems;
said communication processor for HMI operatively connected to a COROS master
system and two numbers of COROS slave systems;
13

said processor means for communicating with other systems operatively connected
to a cooperative PLC with bus coupling with MMC Computer, having a profibus
communication processor; and
said profibus communications processor operatively connected to other PLC/HMI and
Win CC based operator data input and visualization means.
14
4. Human machine interface system as claimed in anyone of claims 1 to 3 wherein said
processor for communication with other computers is adapted such that on receipt of
input data through said interface card the same is analysed and sent to the
processor for HMI, said processor for HMI adapted to put the data in buffer received
from its communication processor (for COROS).
5. Human machine interface system as claimed in anyone of claims 1 to 4 wherein said
COROS HMI is provided with programmable 128 key keyboard for input of operator
data and command.
6. Human machine interface system as claimed in anyone of claims 1 to 5 comprising
means to interface the serial keyboard to Win CC system through COM technology
involving driver software.
7. Human machine interface system as claimed in claim 6 wherein said driver software
comprise Visual Basic/Visual C ++ based driver software.
8. Human machine interface system for control of Hydraulic Down coiler of hot strip mill
substantially as herein described and illustrated with reference to the accompanying
figures.

A HMI (Human Machine Interface) based control system for integrating the hydraulic down
coiler for the Hot Strip Mill (HSM) Automation system in steel plants with rest of the mill, in
simple and reliable manner. The data input and interfacing of operator through a HMI
system to the processor based control system, adapted to function in tandem with the
conventional COROS HMI operating on Master-Slave mode by a parallel system to favour
achieving reliable operation of the system free of any complexities of maintenance/downtime with provision for future upgradation. Common function processors of the system
include processors adapted as (i) router to coilers; (ii) as operator interface;
(iii)Communication Processor for HMI, (iv) common equipment control and (v) processor for
communications with other systems. Importantly, the system of the invention involves
selective data visualization software for better and improved user friendly HMI based
control. The HMI has a customized control and centralized monitoring of all automation
equipments/systems integrated in network, resulting in improved quality and productivity of
HSM.