6.00.00 UNIT CONTROL DESK, UNIT CONTROL PANELS, SYSTEM
CABINETS,LOCAL PANELS & TRANSMITTERS ENCLOSURES/
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
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
6.02.00 CONTROL DESK/ PANEL
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
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
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
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
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
6.03.00 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
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
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
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.
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.