Sub Station Abstract- (Part-3)

 

Electrical Wire Ground Clearance:

  • Ground Clearance in Meter = 5.812 + 0.305 X K

  • Where K= (Volt-33) / 33
Voltage LevelGround Clearance
<=33KV5.2  Meter
66KV5.49 Meter
132KV6.10 Meter
220KV7.0   Meter
400KV8.84  Meter

Overhead Conductor /Cable Size:

Voltage

Overhead Conductor

Cable Size

33 KVACSR-Panther/Wolf/Dog , AAAC150,185,300,400,240 mm2 Cable
11 KVACSR-Dog/Recon/Rabbit , AAAC120, 150,185,300 mm2 Cable
LTACSR-Dog/Recon/Rabbit , AAC,AAAC95,120, 150,185,300 mm2 Cable

 Transmission / Distribution Line:

Span

Height of Tower

400KV=400 Meter

400KV=30Meter (Base 8.8 Meter)

220KV=350 Meter

220KV=23Meter (Base 5.2 Meter)

132KV=335 Meter

220KV Double Circuit=28 Meter

66KV=210 Meter

66KV=13Meter

Conductor Ampere

Voltage wise Conductor

Dog=300Amp

400KV=Moose ACSR=500MVA Load

Panther=514Amp

220KV=Zebra ACSR=200MVA Load

Zebra=720Amp

132KV=Panther ACSR=75MVA Load

Rabbit=208Amp

66KV=Dog ACSR=50MVA Load

Moose=218Amp

 

 Type of Tower:

Type

Used

Angle/Deviation

A

Suspension TowerUp to 2°

B

Small Angle Tower2° to 15°

C

Medium Angle Tower15° to 30°

D

Large Angle / Dead End Tower30° to 60° & Dead End

 Tower Swing Angle Clearance (Metal Part to Live Part):

Swing Angle

Live Part to Metal Part Clearance (mm)

66KV

132KV

220KV

400KV

0°

915mm

1530mm

2130mm

3050mm

15°

915mm

1530mm

2130mm

–

22°

–

–

–

3050mm

30°

760mm

1370mm

1830mm

–

44°

–

–

–

1860mm

44°

610mm

1220mm

1675mm

–

Corona Ring Size:

Voltage

Size

<170 KV160mm Ring put at HV end
>170 KV350mm Ring put at HV end
>275 KV450mm Ring put at HV end & 350 mm Ring put at Earth end

 

Span of Transmission Line (Central Electricity Authority):

Voltage

Normal Span

765 KV

400 to 450 Meter

400 KV

400 Meter

220 KV

335,350,375 Meter

132 KV

315,325,335 Meter

66 KV

240,250,275 Meter

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