| serial no. | Item | unit | FN-12D/630-20 | FN-12R.D/125-31.5 |
| 1 | rated voltage | KV | 12 |
| 2 | rated frequency | HZ | 50 |
| 3 | rated current | A | 630 | 125 |
| 4 | Lightning impulse withstand voltage | KV | | |
| 5 | Power frequency withstand voltage | KV | | |
| 6 | Rated thermal stability current | KA | 20(4S) |
| 7 | Rated dynamic current | KA | 50 |
| 8 | rated closing current(peak value) | KA | 50 | - |
| 9 | rated short circuit breaking current | KA | - | 31.5 |
| 10 | rated displace current | KA | - | 1.5 |
| 11 | max breaking current(reference value) | KA | 1.8 |
| 12 | breaking no-load transformer capacity | KVA | 1250 |
| 13 | Rated cable charging current | A | 10 |
| 14 | Rated load current breaking times | times | >100 |
| 15 | The impactor trigger switch tripping time | S | - | >0.06 |
| 16 | Earthing switch thermal stability current | KA | 20(2s) | 20(2s) |
| 17 | Earthing switch thermal stability current(peak value) | KA | 50 | 50 |
| 18 | Motor operating power supply voltage | V | AC220\DC48 |
