The three-phase SIRIUS line covers the range from 50kVA to 4000kVA and allows for the choice of several
input voltage variation percentages within a broad range (from +30% up to -45%).
The SIRIUS type voltage stabilizers are supplied with independent regulation on each phase.
The SIRIUS type is used when the main is unbalanced and when unbalanced three-phase loads and/or
single-phase loads need to be supplied. In this situation the presence of the neutral wire is required.
The stabilizers are air cooled (natural convection with cabinet internal temperature lower than 400 C).
The measuring instrumentation for the SIRIUS stabi lizers is incorporated in a control panel on the cabinet
door and consists of two mUlti-task digital network analysers. Such instruments are able to provide with
information regarding the status of the lines upstream and downstream the voltage stabilizer such as
phase and linked voltages, current, power factor, active power, apparent power, reactive power, etc.
The information concerning the output line can also be monitored on a remote PC via an RS485 output, an
RS485fRS232 converter and a special software package (supplied with the unit).
Pilot lights are provided for each phase signaling 'power on', reaching of voltage regulation limits and direction
of voltage regulation (increasefdecrease).
Alarms for minimum and maximum voltages, maximum current, over-temperature and ventilation failure
are also indicated. The alarm indicators are accompanied by an acoustic alarm.
All these signals are located on the control panel mounted on the cabinet door and consist of sets of
LEOs.
The line supplying the voltage regulator is provided with an automatic by-pass.
The circuit works in case of temporary overload: It opens the connection between the voltage regulator and the buck/boost transformer and short-circuits the transformer primary winding at the same time.
By doing so, the transformer voltage drop is cancelled and the user can be supplied the main voltage (although not stabilized) without interruption.
The auxiliary circuit is protected by fuses.
The logic control, performed on the true rms voltage, is based on the 2-way OSP microprocessor. By using this device, monitoring the system and setting the stabilizer parameters via a PC connection are made possible.
