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6.01.00  GENERAL


6.01.01  All  unit  control desk/panels, system  cabinets,  local


         panels  &  local instrument  enclosures/racks  shall  be 


         furnished  fully  wired  with  necessary  provision  for


         convenience       outlets,      internal       lighting,


         grounding, ventilation,  space  heating,  anti  vibration


         pads,  internal  piping & accessories  as  per  specn.as


         required for completeness of the system.


6.01.02  All  panels/desk/cabinets shall be free standing type  &


         have bottom entry for cables unless otherwise specified.


         The  bottom  of desk panel/cabinet/enclosures  shall  be 


         sealed  with bottom plate, compression cable glands  and


         fire  proof sealing material to prevent ingress of  dust


         and  propagation of fire.


6.01.03  All electronic system cabinets shall be designed for  50


         Deg.C.operating   under  maximum   ambient   temperature


         without  air  conditioning system in  service.   Further


         cabinets/panels shall be so designed that temp.rise  due


         to  heat  load does not exceed 10  Deg.C  above  ambient


         temp.   under  all  operating   conditions.    Necessary


         louvers/fans, limited packing density, adequate  spacing


         between  instruments/ devices etc.shall be  provided  to


         maintain temp.rise within permissible limits.


6.01.04  Desk/Boards/panels/cabinets enclosures wiring and piping


         shall   be   arranged   to  enable   the    removal   of


         instruments/devices without  unduly disturbing them.


6.01.05  All    panels/desk/enclosures   interiors    shall    be 


         illuminated with rapid start fluorescent strip  fixtures


         with  door  actuated  switches.  Door  switch  terminals


         shall  be  shrouded.  All illuminated  lights  shall  be 


         provided  with individual switch in parallel  with  door




6.01.06  Sufficient  No.of   power  receptacles  with  disconnect


         switches      shall      be       installed       within


         panels/desk/enclosure & racks.


6.01.07  Bidder shall provide the unit control desk(UCD)and  unit


         control panel(UCP) to be mounted in the central  control




6.01.08  The local instrument enclosures/racks shall be  provided


         locally  for  mounting of  electronic  transmitters  and


         switches, etc.


6.01.09  All  panels/desk/cabinets  shall be  properly  grounded. 


         The grounding scheme shall be as approved by Employer.


6.01.10  Exterior  steel  surface shall be sand  blasted,  ground


         smooth, filled, primed, sanded and smooth enamel painted


         to give a good finish subject at minimum paint thickness


         of  65-75  microns for sheet thickness of 3  mm  and  50


         microns for sheet thickness of 2 mm.  Minimum 2 coats of


         primer  and two sprays of final finish colour  shall  be 


         applied to all surfaces.


6.01.11  The  colour of the  panels shall be  brilliant white  in


         the  panel interior. External  colour of the panels will


         be  as  RAL  7032 for UCB/UCD,LIE/LIR and  other  CER  &


         offsite mounted system cabinets, etc.


6.01.12  Due  consideration shall be given to the  ergonomics  of


         unit  control desk, unit control panel and  the  control


         room design.







6.02.01  GENERAL The exact  dimensions, material, construction  details


         etc.of  control  desk/panels etc. shall be  as  per  the 


         actual   requirement  and  shall  be  finalised   during


         detailed  engineering.  The general arrangement  of  the 


         desk/  panel  shall also be  finalised  during  detailed


         engineering, subject  to employer’s approval. The design of all control panels shall take due regard


         of  the  actual application of various devices.   It  is


         important that controls and indications required by  the


         operator  for a particular operation should  be  grouped


         together.   The  bidder  must pay particular  attention  in  the 


         positioning  of  desk  mounted  CRT’s  and  large  video


         screens in relation to control room lighting in order to


         minimize reflections.  For board/ panels/desk  mounted  instruments/devices,


         etc.  which  are to be  powered from UPS,  all  required


         conversion of interface equipments/ accessories to  make


         such  devices  compatible  with  UPS  supply  shall   be


         provided.    All   necessary   hardware    like    input


         switches/fuse  unit  for each feeder as well  as  switch


         fuse  unit  for  each instrument/ device  on  the  power


         supply  line  shall be provided. From UPS,  two  feeders


         shall  be   provided along with suitably  rated  MCB  and


         provision of fast auto changeover of UPS feeders.  Power


         supply  distribution  scheme  shall be  as  approved  by


         employer during detailed Engg.stage.






         Unit control desk shall be free standing table top  type


         with doors at the back and shall be constructed of 3  mm


         thick   CRCA  steel  plates.   All  operators  CRT’s   &


         keyboards shall be mounted on this UCD.  PA System  hand


         sets,  telephone sets and alarm annunciation  PBs  shall


         also  be  mounted.  Few A/M stations & PB  stations  and


         lamps may also be mounted on the control desk on  mosaic


         grid  structure if found necessary.  The desk  shall  be 


         arranged in an continuous arc shape. The exact   profile


         of the desk, dimension and the radius of curvature shall


         also be finalised during detailed engineering stage.


         To  achieve durable & water resistant finish, a coat  of 


         “Polyuthesive  crystal  clear” on the  surface  of  unit


         control   desk shall be  provided.  Final  paint  finish


         with proper smoothening is to be  ensured.  Final finish


         of  UCD should be  in line with relevant  international






         UCP  shall be free standing vertical panel  with  double 


         leaf hinged doors at the back. It shall be constructed of


         3 mm thick CRCA steel plates with mosaic grid  structure


         on front surface.  The mosaic grid tiles shall be  of 24


         mm x 48 mm (or 25 mm x 50 mm) size, made of heat & flame


         retardant,   self  extinguishing   and   non-hygroscopic


         material  with  flat matt finish without glare  and  non


         reflecting  type.  The UCP shall also be arranged is  an


         continuous  arc shape.  The profile and dimensions  i.e.


         radius  of curvatures shall be decided  during  detailed





         All  conventional back up devices/instruments and  large


         video  screen  shall be provided on UCP.   For  mounting


         items,  like  PB  stations,  A/M  station,  miniaturized


         control  switches,  indicators,  recorders  annunciation


         windows,  electrical mimic diagram, on mosaic grid,  the


         size   of   all  these  devices/instruments   shall   be


         compatible to mosaic grid on UCP.


         The  mosaic grid construction should be flexible  enough


         to  allow  easy shifting at site  of any  instrument  on


         mosaic  grid (including indicators & recorders)  to  any


         other  free  location  on the UCP without  any  need  of


         cutting or special equipment/ tool.


6.02.04  The  status  indication  and  repeat  annunciation   for 


         locally   controlled   systems  like  service    air   &


         instrument  air  compressors, DM water pumps etc.  shall


         be   provided  on  UCP  of  unit  No.1  with   important


         parameters  being  duplicated  in unit  No.2  also.  All


         required   miniaturized  control  switches,   electrical


         meters,  associated  mimic  diagram  for  achieving  the 


         control of station electrical system shall be   provided


         in the UCP of unit. The exact number & location of these


         shall  be  as   finalised  during  detailed  engineering






6.03.01  Smoke  detectors  shall  be   provided  inside  the  CER


         mounted system cabinets.


6.03.02  The  cabinets/ panels shall be  provided with eye  bolts


         for fitting.


6.03.03  Feeder  failure/healthy indication shall be provided  in


         each  cabinet & remote indication shall be hooked up  to


         DDCMIS/annunciation & suitably grouped.

6.03.04  The  dimensions  &  load  of  all  panels,  cabinets   &


         enclosures shall be clearly  brought out in the offer  &


         the  same  shall be supplied as  per  employer  approved


         drawings during detailed engineering.


6.03.05  The  local panel/ system cabinet sheet  steel  thickness


         shall not be less than 2.0 mm & that of enclosure  shall


         not be les than 3.0 mm unless otherwise specified.


6.03.06  All  panels/  enclosures/ system  cabinets/  marshalling


         cabinets  shall be provided with a minimum of 20%  spare


         terminations and system cabinets shall be  provided with


         spare space for 20% additional modules fully wired  with


         connectors  etc. in excess of the total  requirement  of


         the system design when the  cabinets are delivered.  The


         spare   space  capacity  shall  be  distributed   evenly


         throughout the cabinets.




6.04.01  Transmitters  and switches, devices etc. mounted in  the


         field  shall be  suitably grouped together  and  mounted


         (i) Local instruments enclosure in case of open areas of


         the   plant  like  boiler  area,  etc.&   (ii)In   local


         instrument racks in case of covered areas.  These  local


         instrument enclosures & racks shall be furnished as  per


         the   actual  requirements  finalised  during   detailed


         engineering stage. 


6.04.02  The enclosures shall be constructed of 3 mm sheet  plate


         &  shall  be of modular construction with  one  or  more


         modules & two end assemblies bolted together to form  an


         enclosure.  The enclosure construction & material  shall


         be  generally  as  indicated.  Gaskets  shall  be   used


         between all mating sections to achieve protection  class


         of IP-65.


6.04.03       The  instrument  racks shall  be  free standing type


Constructed of suitable 5 mm thick channel frame of


steel and shall be provided with a canopy to protect


         the equipment  mounted in racks from falling objects,         


         water etc.  The canopy shall not be less than 3 mm        


         thick steel,  and  extended beyond the ends of the rack. 


         Bulk heads, especially designed to provide isolation from


         process   line  vibration  shall  be   provided.   Exact


         fabrication   details  shall  be  as  finalised   during


         detailed   Engg.stage.  However,  the   same  shall   be


         generally as indicated. The junction box for racks  also


         shall conform to IP-65 protection class.


6.04.04  It shall be possible to start Turbine/Gen DC oil pumps from  control desk control room in the event of failure of DCS.


6.04.05 (a)Minimum No.of back-up instrumentation and  UCP  mounted


         secondary  instruments  per  unit to be  provided  as  a


         minimum are given below.  However, bidder  has to supply


         all  the  required back-up instruments and  UCP  mounted


         secondary instruments on as required basis as  finalized


         during detailed engineering.


          1. Hand/ Auto Stations                :  80 Nos.

          2. Dual scale Indicator(48×48 mm)     :  80 Nos.

          3. Single side Indicator(48×48 mm)    :  15 Nos.

          4. Digital Indicator(24×48 mm)        :  15 Nos.

          5. Control Switches                   :   5 Nos.

          6. Indicating Lights                  :  35 Nos.

          7. P B Stations                       :  75 Nos.

          8. Push to glow lamps                 :  30 Nos.

          9. LED Indicating Tiles               :  45 Nos.

         10. Selector Switches                  :   5 Nos.

         11. 10 Position Miniaturized           :   5 Nos.

             Selector Switch

         12. 3 Pen Recorder                     :   6 Nos.

         13. 6 Point Recorder(Chartless)        :   6 Nos.

         14. 30 Point Microprocessor            :   6 Nos.

             based Recorders (Chartless)

         15. Indicator Analog Digital           :  60 Nos.

         16. Motor Current Ammeters             :  50 Nos.


      (b)The size of all above instruments shall be as per DIN Standard. 


6.04.06  Monitoring Philosophy


     (a) Indicator/Recorder shall be provided on UCP only for few


         critical parameter satisfying the following guide lines.


      i) All   Analog  parameters  which  are  responsible   for


         tripping of unit, Boiler, Turbine, generator, G T.


     ii) All Turbovisory parameters of turbine.


    iii) Few important parameters.


     iv) Parameter corresponding to important control loops.


      v) Parameter  which  are responsible  for  improving  plant




     vi) Ammeter  for  all 6.6 KV, motor  pump/ fan and AC/DC oil 


         pumps motor for generator, turbine etc.


    vii) Recommended by equipment manufacturer.


     (b) In  addition to CRT/KB, for safe shutdown of plant,  for


         handling of emergency for safety of plant,  miniaturized


         push  button,  important A/M  Station,  Lamps,  Selector


         Switch   and   instrument   recommended   by   equipment


         manufacturer, shall be provided on UCD/UCP.


6.04.07  Philosophy for Analog/ Digital Indicators


    (a)  For  slow  changing parameter  i.e.  SH/RH  Temp.Digital


         indicator shall be provided.


    (b)  For  fast changing parameter analog indicator  shall  be


         provided i.e. drum level, furnace draft.



6.04.08       Terminal block


All terminal blocks shall be screwless cage clamp type of  wage/ phoenix make.

6.04.09       Door lock &  hinges  shall be provided for all cabinets/panels/ junction boxes.

6.04.10       Cooling fan & filters – In case where cooling fans are required to keep the cabinet electronics at reasonable  operating temperature.  Bidder shall provide 100% redundant fan. Bidder shall provide fire retarded, washable filter to remove air borne contamination.


6.05.00  All cabinets/ Panels/ Racks shall be with suitable       

         canopy at all the  top to prevent ingress of dripping



6.06.00   Protection class for Panels/Cabinets/Junction Boxes.


a)          Outdoor Location  – IP 65


b)          Indoor Location   – (Non Air Condition)


i)              Non Ventilated – IP 54


ii)          Ventilated     – IP 42


    c)   Air Conditioned Areas (in side  Control Room) – IP 22. 





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