Technical Specification for 66kV Isolator
1. Introduction
CEC requires 66kV isolators (to be adapted on the existing structure) for use on its electrical network.
Therefore, We are inviting bids for the supply of the 66kV isolator (disconnector) from reputable
companies, in accordance with the technical specifications and datasheets below.
2.
Instructions to Bidders
a. Bidders MUST fill in the column marked “Guaranteed Particulars” in this document.
b. Bidders MUST furnish performance record in service of the types of Isolators (Disconnectors)
being offered (reference list)
c. All relevant documentation including technical data sheets and quality accreditation must be
provided with the submitted bids.
3. General Requirements
a)
Isolators (and earth switches where applicable) shall be capable of withstanding the
dynamic and thermal effects of the maximum possible short circuit current on the
system in their closed position. Isolators shall be constructed such that they
cannot be dislodged from their open or closed positions by gravity, wind pressure,
vibrations, shocks or accidental touching or breaking of the connecting rod of the
operating mechanism and do not open under the influence of short circuit.
b)
Isolator shall have pad locking arrangement in both “Open” and “Closed”
positions.
c)
Control cabinets shall be sheet steel enclosed and shall be dust, weather and
vermin proof. A suitable illumination lamp and a 15A 3 pin socket outlet
all with ON and OFF switches shall be provided. Control cabinets shall be mounted on the extreme
ends of the isolator.
d)
Isolator interlocking shall be provided between main isolator and earth switch. All
interlocks shall be designed to prevent mal-operation.
e)
Each isolator shall be provided with a mechanically driven auxiliary switch with
all necessary contacts for control, indication, interlocking. All contacts from the auxiliary switches
shall be brought out to a terminal block housed in the mechanism box.
f)
During the course of normal operation, it is likely that the isolator may be left in
the Open/Closed positions for long periods of time. They shall be designed to
operate satisfactorily even after being kept in one position for a long period.
g)
Nameplate information shall be visible in the position of normal service and installation
4.
Site Operating Conditions
Altitude above mean sea level
Maximum ambient temperature for design purposes
Average ambient temperature for design purposes
Minimum ambient temperature for design purposes
Relative humidity maximum at 35oC
Maximum wind speed
Earthquake loading for design purpose
Mean annual rain fall
Maximum solar radiation W/m2
Isokeraunic Level average days/year
1400m
40oC
30oC
-1oC
95%
40m/s
N/A
1065mm
1200
130
5. 66kV Disconnector technical data sheet
66 kV Disconnector - TECHNICAL SPECIFICATION SHEET
Particular
Description
Unit
Requirement
No
1 Make
Any
Standards
IEC 62271-102
Horizontal, Three
phase double break
2 Type
3 Service
a)
Outdoor
Application
4 Rated System Voltage
Offload
kV rms
66
5 Highest System Voltage
Kv
72.5
6 Rated frequency
Hz
50
A
1200
A
1200
8 Rated short time withstand current, I (3 sec)
symmetrical
kA rms
31.5
9 Rated peak withstand current
kA peak
*
-
Solidly earthed
V rms
Solid core
100
A
kV
1200
7 Rated Normal Current
a) ALL disconnectors with earth
switches and ALL disconnectors
without earth switches.
b) (2) Disconnectors without earth
switches
10 System Earthing
11 Type of support insulators
Rated bus transfer Voltage
12 Insulation level – support insulators
Rated Bus transfer current
a) Rated 1 min power – frequency
withstand voltage
i.
Dry
kV rms
140
ii.
Wet
kV rms
140
b) Lightning impulse withstand
voltage
kV peak
325
Guaranteed
Particulars
66 kV Disconnector - TECHNICAL SPECIFICATION SHEET
Description
Unit
Particular
Requirement
No
c)
Switching impulse withstand
voltage
kV peak
As per IEC standard
kV rms
140
kV rms
*
kV rms
325
kV rms
*
kV rms
As per IEC standard
kV rms
E1
mm
As per IEC standard
As Per IEC standard
Min 1800
mm
1200
mm
>650
mm
As per attached
drawing.
13 Rated 1 min power – frequency withstand
voltage complete disconnector
a)
To earth
b) Across open switching device
14 Rated lightning impulse withstand voltage
a)
To earth
b) Across open switching device
15 Rated switching impulse withstand voltage
a)
To earth
b) Across open switching device
Electrical Endurance
16 Minimum creepage distance
17 Minimum electrical clearances
a)
Between phases
b) Between phase and earth
18 Phase to phase spacing adopted in the
layout
19 Operating mechanism
a)
Motor drive (Both
Manually and
Electrically driven)
No. per disconnector
b) Motor operating supply
1
VDC
110
Rated output of motor
W
*
d) Maximum starting current
A
*
c)
e)
Operating times
Guaranteed
Particulars
66 kV Disconnector - TECHNICAL SPECIFICATION SHEET
Description
Unit
Particular
Requirement
No
i.
Opening
*
ii.
Closing
*
20 Interlock between main switch with
earthing switch
Electrical and
Manual
21 Auxiliary switches
i.
Number and rating
(Disconnector)
ii.
8 Normally Closed
and 8 Normally
Open (for CEC use).
40-110VDC / 100220VAC
Earth switch (Status
indication)
Yes
22 Control cabinet
a)
Thickness of sheet metal
mm
IP 65 as per IEC
60529
b) Enclosure protection
c)
Enclosure heating power
consumption at 220 V AC
d) Painting
23 Maximum temperature of current carrying
parts when carrying rated current
continuously
3
W
*
-
Synthetic enamel
paint of approved
shade
oC
90
-
*
-
Copper and Copper
alloy
As per IEC standard
24 Type of material of current carrying parts
a)
Type of main and arcing contacts
b) Material of contacts
i.
Main
Mechanical Endurance
c)
Whether contacts are silver plated,
Yes / No
M1
-
Yes, shall be more
than 25 microns
Guaranteed
Particulars
66 kV Disconnector - TECHNICAL SPECIFICATION SHEET
Description
Unit
Particular
Requirement
No
25 Torque required to operate each pole
N
Guaranteed
Particulars
*
26 Insulator data (for complete stack)
a)
Type
Porcelain
b) No. of units
c)
Height of stack
27 Total weight of disconnector
28 Outline drawing supplied
One (01)
mm
*
Kg
*
-
Yes, include pdf and
CAD drawings
29 Independent testing authority certificates
held to prove type test ratings to IEC
requirements
Yes, to be provided
30 Isolator to suit existing structure
31 Provide Clamps
32 Number of disconnectors
Yes
Set as necessary
per phase
(conductor sizes
for Cu 124mmsq)
Yes
10 Line
disconnectors
complete with earth
switches.
18 disconnectors
without earth
switches.
Note: Items marked (*) to be furnished along with the bid and appropriately filled in under the column marked
“Guaranteed particulars”.
SYSTEM MAINTENANCE
66KV ISOLATOR REPLACEMENT
No
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
Line
Isolator/Earth
switch
Comments
CIRCUITS
MBBI/BBI RBBI
Avenue - Mimbula TEE 66kV line
unic
Avenu -Bancroft 66kV Line
1
Kabundi - Luano 66kV Line
1
Kabundi - Stadium 66kV Line
1
Nkana - CSS 1 66kV line
1
Nkana - CSS 2 66kV line
1
Nkana - Bus section Isolator No. 1
1
Fikondi Tx 2 Bus Section Isolator
1
Kansuswa - Kankoyo 1 66kV Line
1
Kansuswa - Kankoyo 2 66kV Line
1
Kansuswa - Mufulira 66kV Line
1
Kankoyo - Muf West 66kV Line
1
Roan - Tx 2 66kV Bus Section Isolator
1
Roan - Luanshya Munic 66kV Bus secti
1
Roan - Iwin 66kV Bus bar Isolator
1
Roan - Tx 4 66kV Bus section isolator
1
Luanshya Munic - Storke 66kV Busbar
1
Totals
Subtotal
2
QUANTITY
18
10
10
10
28
SUMMARY OF QUANTITIES
1
1
1
1
1
1
1
1
1
1
16
18
Grand totals
DESCRIPTION
Old Busbar Isolators
Old Line Isolators c/w Earth switches
1
1
Old isolators
Old isolators
Old isolators
Old isolators
Old isolators
Old isolators
Old isolators
Old isolators
Old isolators
Old isolators
Old isolators
Old isolators
Old isolators
Old isolators
Old isolators
Old isolators
Old isolators