132kV On-load Tap
Changer TYPE–ABS132
ABS132 OLTC is a single compartment externally mounted on-load tap changer. This OLTC works on the principle of high speed transition resistance and is applied at the neutral end of 3 phased, star connected transformers. The tap changer is equipped with a change over switch and will therefore suit either reversing or coarse fine type tapping equipment. The OLTC follows the principle of flag cycle thus making it suitable for bi directional flow of power.
Advantages
- It has a compact design, easy maintenance and low oil requirement.
- The tap changer is protected by an oil surge protective relay (OSR) which is connected to a conservator.
Key Features
- The complete tap changer unit with the drive mechanism and the selector switch chamber are housed in a sheet metal enclosure, with a flange for mounting on the port on the transformer tank.
- The fixed contacts are mounted on the phase boards. The selector switch, one for each phase, moves over these fixed contacts and selects the tap.
- The selector switch comprises a main contact and two auxiliary contacts and combines the functions of tap selector and a diverter switch.
- The drive mechanism is coupled to the selector switch by drive shafts and a series of gears.
- It comprises a motor reduction gear, dial switch for tap position indication, limit switches for stopping the motor at end positions, operation counters, and hand drive for emergency operations.
- It also has an energy storage spring whose sudden release of energy operates the selector switch.
Specifications
- Rated voltage: 132kV (Graded neutral)
- Max. rated through current: 300A
- Max. rated step voltage: 1200V
- Rated insulation level: 140kV power frequency and 350kVp impulse
- Max no. of tapping positions: 17 with change over switch
- Tapping arrangement: Change over (reversing/coarse-fine)
- Cycle of transition: Bi-directional flag cycle
- Total weight with oil: 1810 kgs
- Oil content: 1400 litres (approx.)
