6.UNIT CONTROL DESK, UNIT CONTROL PANELS

6.00.00  UNIT CONTROL DESK, UNIT CONTROL PANELS, SYSTEM

        CABINETS,LOCAL PANELS & TRANSMITTERS ENCLOSURES/ 

        RACKS

 

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

 

         switch.

 

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

 

         rooms.

 

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.

 

 

 

 

6.02.00  CONTROL DESK/ PANEL

 

6.02.01  GENERAL

 

6.02.01.01 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.

 

 

6.02.01.02 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.

 

6.02.01.03   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.

 

6.02.01.04  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.

 

 

 

6.02.02  UNIT CONTROL DESK (UCD)

 

         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

 

         standards.

 

6.02.03  UNIT CONTROL PANEL (UCP)

 

         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

 

         engineering.

 

 

         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

 

         state.

 

6.03.00  CABINETS/ ENCLOSURES/ PANELS

 

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.

 

6.04.00  LOCAL INSTRUMENT ENCLOSURE AND RACKS

 

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

 

         efficiency.

 

     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

         water.

 

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.