Siemens has more than 30 years of experience in vacuum switching technology and is a leader in the field of digital protection technology. The 3AD 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 3AD 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