BIS 1000 model in the line-interactive UPS series is equipped with a multi-tap variable-voltage autotransformer. This autotransformer can add or subtract powered coils of wire in order to increase or decrease the magnetic field and the output voltage of the transformer. The line-interactive circuit topology in the UPS ensures high efficiency. BIS 1000 has the capacity to load two computers. The UPS has Automatic Voltage Regulation (AVR) range of 145-280V and battery low voltage automatic shutdown function. BIS 1000 UPS offers protection against over-voltage and under-voltage protection.