Technical Specifications – 11kV Incoming Outgoing (ICOG)
Panel – 630 Amps
S. Item Description Specification Details
No.
1 Panel Type Floor Mounted, Indoor, Metal Clad, Standalone,
Cubicle Type, Horizontal draw-out and
Horizontal Isolation VCB Type.
2 Design Totally Enclosed, Busbar Based, Flush Front
3 Application 3Phase, 11KV (unearthed), 50 Hz, 630Amps.
Operating Voltage: 11KV ±10% and
Frequency: 50Hz±3%.
4 VCB (Vacuum Circuit a. Draw-out Type.
Breaker) b. Manual/Motor operated spring charging
with 230V AC motor.
c. Trip and close coils (24VDC), Auto safety
shutters, Manual push buttons.
d. Operating Sequence: 0-0.3S-CO-3min-CO.
5 VCB Characteristics Breaking Capacity: 40kA
Making Capacity: 100kAp
Short Circuit Withstand Capacity: 40kA for
3 Sec.
Internal Arc Withstand: 40kA for 1 Sec.
Insulation: 75kVp Impulse, 28kV Power
Frequency
6 PT (Potential Three-phase segregated fixed type PT with HT
Transformer) PT Fuses. Ratio: 11kV/√3 – 110V/√3. Class: 0.5,
Burden: 100VA
7 CTs (Current Single Phase CTs (03 Nos.) – Ratio: 150/1-1A;
Transformers) Core 1: Metering: Class 0.5, 15VA; Core 2:
Protection: Class 5P10, 15VA. CT and VT
Burdens to be calculated and justified. CBCT:
50/1 For Earth fault protection.
8 Instrumentation Voltmeter (15kV range), Ammeter (Analog)
MFM with Modbus or any other for KW, KWh,
PF and KVA.
9 Protection Relays Numerical Relays (IDMT + Inst.) for Over
Current & Earth Fault: 50, 50N, 51, 51N; with
CBCT; Master Trip Relay (86); Transformer Aux
Protection Relays
10 Indications & Control ON/OFF/Auto Trip/Spring Charged/Trip Circuit
Healthy/Test/Service Lamps; R-Y-B Phase
Indication Lamps; Emergency Stop Push
Button, Control Supply Available/Incoming
Supply Available.
Control: TNC Switch with Lock
Local/remote Selector Switch
Remote Close/Trip via Interposing relays.
11 Control Wiring CT: 2.5 sq.mm RYBG.
PT: 1.5 sq.mm RYBG.
AC: 1.5 sq.mm Black.
DC: 1.5 sq.mm Grey. All with appropriate
MCBs (AC/DC 2P MCBs), 1P MCBs for
Heater/Motor, PT Sec: 4P MCB
12 Panel Bus Bar 630 Amps copper bus bar with heat-shrinkable
PVC insulation
13 Earth Bus GI Bus Bar 50mm x 6mm, Single Run
14 Enclosure MS Sheet Steel (1.6mm/2mm thick), RAL-7032
Color, Glossy Finish; Suitable for indoor use
with base channel; IP-4X protection;
15 Power Backup Unit 110VAC/24VDC Power Pack with battery
backup sourced from PT supply; Supports
multiple trip-close operations for 45 minutes
minimum; also supplies 220VAC spring charge
motor during mains failure
16 Cable Entry & Bottom entry with undrilled gland plates of
Termination minimum 3mm thickness for minimum 3 Nos.
300 sq.mm 11kV (UE) AL XLPE FRLS/PVC
cables.
Outdoor terminal box with side exit holes,
suitably extended for proper termination.
Rear Mesh cover for safety
Space for Proper cable routing and
termination.
17 Fuses No glass fuses allowed. Only MCBs of
2A/4A/16A
18 Interlocks and Safety Electrical & Mechanical interlocks for doors
and VCBs.
Rear door interlock to generate trip.
Interlocked for no operation if VCB is ON and
door is open.
Danger Symbols, IR Windows for
thermography
19 Preferred Panel Width Minimum 750 mm (other sizes acceptable with
OEM short circuit/current certification)
20 Testing & Internal Arc tested (40 kA / 3 sec, 1 sec
Certification duration),
Type tested as per IEC 62271-100/200 /
IS13118 (1991 or latest),
OEM certified panel test reports to be
submitted
21 Documentation to be OEM Certificate, Technical Datasheet, GTP,
Submitted Operation Manuals, GA Drawings, Test
Certificates, Product Manual, Tentative Type
Test Reports
22 Inspection & Approval Pre-dispatch inspection by NTPC. Prior notice
of one week. Panel to be manufactured and
tested at OEM works (if through dealer). Type
tested panel reports (within last 5 years) to be
submitted
23 Standards IS/IEC: 13118, 2705, 3156, 61869-2/3, 62271-
Compliance 100/200
24 Spares to be supplied 1 No. Each: CT, PT, Ammeter, Voltmeter, MFM,
Auxiliary Relays, Selector Switch, Contactor,
Tripping Coil, Closing Coil, Spring Charging
Motor, CAM Switch
25 Guarantee Minimum 12 months replacement guarantee
from date of material receipt for
manufacturing defects or 18 months from
delivery (Whichever is earlier).
