SDF Series Horizontal center break disconnector
Key attributes
| Brand | ROCKWILL |
| Model NO. | SDF Series Horizontal center break disconnector |
| Rated voltage | 420kV |
| Rated normal current | 4000A |
| Rated short-time withstand current | 63kA |
| Series | SDF Series |
Product descriptions from the supplier
Description
Overview
The SDF disconnectors are available for up to 550 kV, 4000 A and 63 kA. These type of disconnector have a low friction design and offer minimized contact resistance. They are equipped with dead center interlocking for reliability in extreme conditions. Some other important features of these disconnectors are
No external spring in contact fingers
Superior design of mechanical interlock
Strong rotary pedestals
Ice breaking capacity
Applications
The horizontal center break disconnector is used at substations due to its simplicity and flexibility in arrangement.
Technology Parameters
Rated voltage (kV) |
72.5 |
123 |
145 |
245 |
300 |
362 |
420 |
550 |
Rated current (A) |
4000 |
|||||||
Short time withstand current (kA) |
63 |
|||||||
Power frequency withstand voltage (kV) |
||||||||
against earth |
140 |
230 |
275 |
460 |
395 |
450 |
520 |
620 |
across isolating distance |
160 |
265 |
315 |
530 |
435 |
520 |
610 |
800 |
Lightning impulse withstand voltage (kV) |
||||||||
against earth |
325 |
550 |
650 |
1050 |
1050 |
1175 |
1425 |
1550 |
across isolating distance |
375 |
630 |
750 |
1200 |
1050 |
1175 |
1425 |
1550 |
Switching impulse withstand voltage (kV) |
||||||||
against earth |
|
|
|
|
850 |
950 |
1050 |
1175 |
across isolating distance |
|
|
|
|
700 |
800 |
900 |
900 |
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