De-energized linear tap changer
WST (WDT) de-energized, linear tap changer
ZH2：De-energized combined linear triple-phase tap changer (a 1set for 2 pieces combination)
Sample：WSTⅣ63/10-6×5ZH2
It is combined by 2 operating pieces of a WSTⅡ63／10-6×5 and a WSTⅣ63／10-3×2
ZH3: De-energized combined linear triple-phase tap changer (1 set for 3 pieces combination)
Sample：WSTⅤ63／20-6×5 ZH3
It is combined by 2 operating pieces of a WSTⅤ63／20-5×2 and 2 WSTⅡ63／20-6×5
F：--- Reversing installed linear switch
G：---Switch for dry-type transformer
D：---double-sealed switch（Each one on the top of and below the tank cover of transformer）
Technical Data
The tap changer applies to single-phase , triple-phase oil-insulated transformers of the frequency 50Hz, 60Hz, of the highest voltage for equipment 10KV-35KV, of the rated through-current 30A-500A,fixed on tank cover of transformers directly and exchanged in the de-energized state. Voltage regulation positions (center, terminal, neutral point).
| Specificatons | WST | WST | WST 125 | WST 250 | WST 400 | WST 500 | |
| 30 | 63 | 125 | 250 | 400 | 500 | ||
| Connection mode | Central point(Ⅱ)Neutral Point(Ⅲ)Terminal Point(Ⅰ) | ||||||
| Rated throughcurrent(A) | 30 | 63 | 125 | 250 | 400 | 500 | |
| Short-circuit capacity | Heat stableness current(kA/2s) | 0.7 | 1.6 | 2.5 | 3.75 | 4 | 5 |
| Dynamic stableness current(kA) | 1.8 | 4 | 6.25 | 9.375 | 10 | 12.5 | |
| Rated frequency（Hz） | 50～60 | ||||||
| Insulation level(kV) | Highest voltage（kV） | 10kV | 20kV | 35kV | |||
| Power-frequency withstand Voltage（50Hz／1min) | 42kV | 55kV | 95kV | ||||
| Impulse（1.2／50μs) | 75kV | 125kV | 250kV | ||||
| Sealing Performance（kPa/24h） | 60 | ||||||
| Machine life(Thousands of times) | 2 | ||||||
| Thickness of transformer tank cover： （1）Opening holeΦ20.5+0.5Applying to3～8mm tank cover;（2）63/10～20 Applying to 5～8mm tank cover;（3）125/10～20 Applying to 6～10mm tank cover;（4）250/10～20 Applying to 8～12mm tank cover;（5）35kV Applying to 8～12mm tank cover | |||||||