disturbance. Separate battery chargers configured with switch mode power supply technology are responsible for charging or trickle-charging the battery connected in the intermediate circuit. The configuration of these charging rectifiers means the harmonic content of the charging current for the battery is almost zero, which increases the service life of the battery even more. The inverters are responsible for converting the DC voltage into a sinusoidal output voltage. A microprocessor- driven control based on a pulse-width modulation (PWM) integrated in each UPS module guarantees, in conjunction with digital signal processor technology and extremely fast pulsating IGBT power semiconductors of the inverters, a voltage system of the highest quality and availability on the secured busbar.

In the event of mains faults (e.g. current failures), the voltage continues to be supplied from the inverters to the load without any interruption. From this point onwards, the inverters draws their power from the battery instead of the rectifiers. Since no switching operations are necessary, there is no interruption in the supply to the load.

The greatest possible supply reliability of connected loads is attained by the parallel connection of up to max. six PROTECT 1.040 UPS modules. The n+x technology thus guarantees maximum reliability through up multiple active redundancy on the one hand as well as on the other hand the possibility of increased power with simple redundancy or even only higher UPS power without any redundancy.

The automatic electronic bypass serves to increase the reliability of the supply further. It switches the public mains directly through to the load without any interruption, e.g. when there is a system overload. As a result, the automatic bypass represents an extra passive redundancy for the load.

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