The WDGII magnetic minute tap switch manual provides overview, specifications, installation, operation, and maintenance instructions.
This manual describes the WDGII non‑excited magnetic minute tap switch, which is used on oil‑immersed transformers rated up to 110 kV, 1000 A and 50 Hz. It includes a product overview, model description, key technical parameters, structural features, working principle, dimensions, wiring diagrams, and installation guidelines.
Installation, operation, and maintenance procedures are detailed, emphasizing the need for the transformer to be de‑energized and the switch to be dry before use. The document also explains the correct hand‑turning method to ensure reliable contact and provides periodic maintenance recommendations. This manual is written in Chinese.
| Rated frequency | 50 Hz |
|---|---|
| Rated voltage | ≤110 kV |
| Rated current | ≤1000 A |
| Switch models | WDGII500, WDGII1000 |
| Voltage levels (kV) | 35, 66, 110 |
| Maximum working voltage (kV) | 40.5, 72.5, 126 |
| Voltage regulation range | ±2 × 2.5 % |
| Contact resistance | ≤350 µΩ |
| Seal performance | 6 × 10⁴ Pa for 24 h, no leak |
| Mechanical life | >10 000 cycles |
If the voltage is unchanged, the switch should be operated at least once every three years, rotating the hand for more than ten cycles.
Rotate the hand past the indicated position, then reverse to the stop position; this guarantees reliable contact.