Medium Voltage LIS Retrofit
For facilities concerned with arc flash safety standards, the options may seem daunting and the costs out of reach. The fuses used by LIS to protect the transformer in an overcurrent situation are no longer adequate. Existing LIS may provide poor fault current interrupting times, resulting in high arc flash incident energy.
ABB’s solution retrofits a fixed mounted ABB vacuum circuit breaker (VCB) into the fused compartment of the LIS. Operating in three cycles, the fast-acting VCB is superior to fuses and provides a new arc flash mitigation solution designed in response to current arc flash safety standards.
With modifications, ABB can also provide retrofits to other manufacturer's Load Interrupter Switches.
Features and benefits
The medium voltage LIS retrofit solution delivers safety and flexibility to existing equipment, offering:
- Reduced arc flash levels from the transformer down to the low voltage system
- Transformer protection via the latest relay technology (bus and transformer differential protection)
- Added transformer protection via an optional snubber application
- Relay options that provide upstream and/or downstream communications
- Retrofitting into existing LIS enclosure
- Minimal downtime for installation and commissioning (approximately 8-12 hours)
- Added reliability and quality of a fast-acting, 3-cycle vacuum circuit breaker with embedded pole technology
- Separate low voltage door for access during maintenance - without the need to open the high voltage compartment