4. TRANSMISSION LINES
• Extra High Voltage
– 110 kV, 132 kV, 220 kV, 400 kV
• Ultra High Voltage
– 765kV
• High Voltage Direct Current
– ±500kV
5. TRANSMISSION LINES
• Survey is the most important activitySurvey is the most important activity
• Best possible routeBest possible route
• Right of WayRight of Way
• Techno-Economical ProjectTechno-Economical Project
• Timely completion of the projectTimely completion of the project
• Increasing DemandIncreasing Demand
6. PRELIMINARY SURVEY AND WALK
OVER SURVEY
• Topographical map
• Bee line
• Identify possible routes
• Familiarize
• Indicate the feasibile routes
12. DETAILED SURVEY
• Fixing of Alignment
• Fixing of Line Points
• Fixing of Angles of deviation
• Fixing of Angle Points
• Fixing of Direction Points
• Measuring of distance between Angle Points
• Levels at every 10 M interval or where there is level
difference of 30 Cm
13. DETAILED SURVEY
• Details of Roads
• Details of Villages
• P & T Lines Crossings
• All Power Lines Crossings – LT to 765 kV
• Railway Crossings
• River Crossings
• Agricultural wells, Field bunds & Earth bunds etc.
• Measuring Soil resistivity at 1 Km interval
• Trial Pits
• Crop & Tree enumeration
14. DETAILED SURVEY-OBLIGATORY
POINTS
• Avoid
• Reserve Forest Area
• Military Firing Ranges
• Aerodromes
• Inhabited and thickly populated areas
• Hilly terrain
• Marshy, Low lying & Submersible areas
• Higher & 90 degrees angle turnings
• Oil & Gas storage areas
15. DETAILED SURVEY – CORRIDORS
• 132 kV Line 27 M
• 220 kV Line 35 M
• 400 kV Line 52 M
16. DETAILED SURVEY –LINE PROFILES
• Graphical representation
• Scale
X-axis 1 Cm = 20 M
Y-axis 1 Cm = 2 M
• Plot Plan of Alignment of Line from AP to AP
• Plot Distances
• Plot Levels with respect to distance
17. DETAILED SURVEY –LINE PROFILES
• Indicate all Power Lines crossings: LT to 765 kV
• Indicate all P & T Lines crossings
• Indicate all Railway crossings
• Indicate all River crossings
• Indicate all Roads: Cart Tracks to National Highways
• Indicate all Villages
18. DETAILED SURVEY –LINE PROFILES
• Indicate all Agricultural wells
• Indicate all Field bunds & Earth bunds
• Indicate all Boulders
• Indicate all Ponds & Lakes
• Indicate type of Soil
• Indicate Crops & Trees
24. TOWER SPOTTING
• Identify the position of Terminal Tower
• Start from Terminal Tower
• Match the tower footing curve with the position of
TT
• Adjust the position of template
• Ensure Ground Clearance
• Identify the position of next tower
• Move the template to the next tower
• Repeat the procedure
25. TOWER SPOTTING
• NORMAL SPAN: It is the design span
• ACTUAL SPAN: It is the actual distance between
two adjacent towers
• NULL POINT: It is a point in a span where the
position of the conductor is lowest (or) It is a point in
a span where the sag is maximum
• WEIGHT SPAN: The distance between two adjacent
null points
• WIND SPAN: It is the distance between the two
centre points of adjacent spans
26. TOWER SPOTTING –SPAN LIMITATIONS
SPAN 132 kV 220 kV 400 kV
NORMAL SPAN 320 M 350M 400 M
WIND SPAN
Both 320 M 350 M 400 M
Single 192 M 210 M 240 M
WEIGHT SPAN
Both 400 M 450 M 600/800 M
Single 240 M 270 M 300/400 M
27. TYPE OF TOWERS
ANGLE
(in degrees)
132
kV
220
kV
400
kV
0 to 2 P A DA
2 to 15
R
B DB
15 to 30 C DC
Above 30 S D DD
28. TYPE OF TOWERS
ANGLE
(in degrees)
132
kV
220
kV
400
kV
0 to 2 K X MA
2 to 30 L Y MC
Above
30
M Z MD
34. CLEARANCES
132 kV 220 kV 400 kV
Ground Clearance 6.1 M 8.5 M 9.0 M
LT to 132 kV and
P& T Lines
3.1 M 4.6 M 5.5 M
220 kV 4.6 M 4.6 M 5.5 M
400 kV 5.5 M 5.5 M 5.5 M
35. CLEARANCES
132 kV 220 kV 400 kV
Highway Crossing 9 M 9 M 9M
Railway Crossing 14.6 M 15.4 M 17.9 M
Railway Crossing
Span (Max)
2/3 of NS 2/3 of NS 2/3 of NS
Distance between
Tower & Railway
Track (Min)
TH+6 M TH+6 M TH+6 M
36. TOWER SCHEDULES
Location
No.
Type of
Tower
Angle of
Deviation
(degrees)
Span
(M)
Left Wt.
Span
(M)
Right Wt.
Span
(M)
Total Wt.
Span (M)
Remarks
SS Boom - - - - Boom at sending end SS
70
1 TT S 35 L - 75 -
Terminal tower at sending
end SS
210
2 P - 135 150 285
300
3 R 22 R 150 130 280 Near village
280
4 P+3 - 150 125 255 33 kV Line crossing
250
37. CHECK SURVEY
• Marking of Tower Location
• Forward & Backward Line Points
• Pit Marking
• Excavation
39. GLOBAL POSITIONING SYSTEM
• Satellite dependent
• Latitude & Longitude coordinates of the
position
• Starting coordinates and ending coordinates
• Map Source Software
• Google Earth
• Topo sheet can be generated
• Bee Line & Routes can be marked
41. TOTAL STATION
• Similar to Theodolite
• Not dependent on satellite
• Arbitrary Coordinates of the position
• Coordinates of the position obtained from GPS
• Alignment, Distance & Levels are recoded
simultaneously
• Horizontal & Vertical Angles can be recorded
42. TOTAL STATION
• Raw data
• Text
• Auto Plotter
• Auto CAD
• Line Profile can be generated
43. PLS CADD
• Data from Total Station
• Sag calculation data
• Tower Spotting
• 2-D Model can be generated
• 3-D Model can be generated