Siemens distribution recloser (SDR) switch
Up to 38 kV
SDR distribution recloser description and features
Siemens has more than 30 years of experience in vacuum switching technology and is a leader in the field of digital protection technology. The SDR recloser combines cutting-edge technology with quality engineering experience in relay protection schemes for which Siemens is known.
The Siemens 7SR controller constitutes the brains of the recloser. It comprises indicators and control elements, communication interfaces and a USB port for convenient connection of a laptop computer. Access to the user level menus and data is protected by multi level password authentication. Along with overcurrent time protection (49 preset curves and multiple user configurable curves), it is equipped for earth fault and sensitive earth fault detection. Inrush restraint and load shedding are further protection functions that help prevent nuisance outages.
The Siemens 7SR controller offers a multitude of inputs and outputs for customer use. Additional communication modules for data transfer are available as options. Self-monitoring and measuring functions round out the profile. The Siemens 7SR controller is mounted in a cabinet, which also contains the auxiliary power supply and a battery-backed UPS unit, fuses and a general purpose outlet to power a laptop.
Siemens SDR distribution reclosers offer dependable protection for temporary faults in overhead line networks and improve the reliability of power supply systems. The Siemens 7SR controller, the core of the system, provides a high level of protection, easy operation and high operating efficiency.
Ratings through 38 kV
Factory engineered, pre-installed and wired accessories for ease of on-site installation
Advanced vacuum interruption technology
Fully integrated current transformers (CTs) and resistive voltage transformers
Dual-coil, low-energy magnetic actuator
SDR distribution recloser switch technical data and ratings
Rated continuous current | 400 A; 630 A; 800 A |
Rated voltage according to ANSI C37.60 | 12 kV; 15.5 kV; 27 kV; 38 kV |
Recloser sequence | O - T - CO - T - CO - T - CO - lockout T individually settable 0.2-14000s |
Opening time | 30 ms |
Closing time | 60 ms |
Number of switching cycles | 10,000 |
Number of short circuit operations | Up to 200; 166 according to ANSI C37.60 duty cycle |
Number of phases | Three-phase, single phase, triple-single |
Rated voltage (kV) | Interrupting current (kA) (sym) | Lightning impulse withstand voltage (kV) | Continuous current 400 A | Continuous current 630 A | Continuous current 800 A |
12 | 12.5 | 95 | ---- | Yes | Yes |
15.5 | 12.5 | 110 | Yes | Yes | Yes |
15.5 | 16 | 110 | ---- | Yes | Yes |
27 | 12.5 | 125 | Yes | Yes | Yes |
27 | 12.5 | 150 | Yes | Yes | Yes |
27 | 16 | 150 | ---- | Yes | Yes |
38 | 12.5 | 170 | ---- | Yes | Yes |
38 | 16 | 170 | ---- | Yes | Yes |
SDR distribution recloser switch dimensions
Rated voltage Ur | 15 kV and 27.6 kV |
Dimensions: length x width x height in inches (mm) | 46.2 (1173) x 20.5 (521) x 37.9 (962) |
Weight in lbs (kg) | 309 (139) |
SDR distribution recloser switch front and rear photos