7/30/2019 Architecture r 2

http://slidepdf.com/reader/full/architecture-r-2 1/2

Rev.2 Date : 1/12/2000

BAGASSE HANDLING SYSTEM –24 MW CO-GEN PLANT AT SAMEERWADI

WRITE-UP ON CONTROL SYSTEM ARCHITECTURE

The control system will be based on available models of reputed makes of PLC, having all flexible features, which are normally found In large PLC’s.PLC system included will be non redundant type , made up of digital inputand output modules of 16 channels type.

 All the I/O modules, power supply units, etc., are housed in control desk(CD)The CPU along with its power supply and the communication cards are locatedin the PLC cabinet. The status of all pull cord switches and belt sway aswitches for each belt conveyor (contacts of each set connected in seriesseparately), ZSS, the status of the drives (running), bunker levels, etc., arewired to the input interface modules of the PLC located in CD. In addition,

other inputs, such as, mode selection, path selection, drive ON/OFF operationon manual mode using PB’s, etc., which are all mounted on the Control Desk,will also be wired to the input interface modules.

The signals received at the I/O modules communicate with the CPU in thePLC cabinet. The ladder application program (to be developed by PLCequipment supplier) will be loaded in the PLC. The MMI software provided for the system takes these status inputs from the PLC and also from the PCand Keyboard. One monitor for the operator station is also provided.

The outputs, which are activated by PLC’s will drive the output relaysmounted in the control desk. Set of required number of outputs available in

the PLC will be wired up for indication in mimic (part of CD). This will enablethe operator to quickly understand the fault and take remedial action.Separate group communication windows are provided in the mimic panel toidentify whether PCS or BSS or ZSS operated and also which drive hastripped, i.e., correlating the above two, the operator will understand whether aparticular drive has tripped due to its PCS operation. In case, only the drivetrip annunciation comes, then he will understand it is due to its overloadoperation.

 Any fault in the PLC system will also be diagnosed automatically andannunciated.

In addition to the above, all the above will be displayed in the mimic on themonitor.

 Annunciations :  Annunciations are provided as per list furnished separately.

Power Supply

 A 230V UPS power system of adequate capacity shall provide power supplyfor the CPU, PC and also for the I / O interface cards and output relays.

1

7/30/2019 Architecture r 2

http://slidepdf.com/reader/full/architecture-r-2 2/2

Rev.2 Date : 1/12/2000

Interface Wiring Cabling

 All the DI /DO signals from MCC, Local Panels, etc., will be received at theControl Desk. In the case of wiring from MCC, all the DI /DO signals will bechannelled through an interlocking module provided in the MCC, separately for each bus section, i.e., the contacts ‘from’ and ‘to’ the individual drive moduleswill be wired through inter modular wires within MCC itself. Grouped cableswill then take off from this interlocking module to the control desk (PLC).

Other Features

 At least 10% spares of I / O modules are provided in the control desk.

2