HIGHLIGHTS

• The Sirio Centralized and Sirio Centralized HV models have a low frequency isolation transformer
• The Sirio Centralized HV-MT and HHV-MT models are suitable for direct connection to LV/MV transformers
• High conversion efficiency
• Full nominal power up to 45 °C
• Speed-controlled fans to optimize the efficiency
• Colour LCD touch display with datalogger function
• Fully accessible from the front
• 2 expansion slots to connect communication boards
• MCCB AC side and switch DC side
• Suitable for operation with modules that require the grounding of a pole

Centralized inverters are inverters generally used in large photovoltaic systems and are used with the same philosophy as string inverters, only applied on a larger scale.

Sirio Centralized inverters allow direct connection to the low voltage grid ensuring the galvanic separation compared to direct current installations. The generous rating of the transformer and the other inverter components provides a return of the highest among the machines of the same category.

In order to increase overall plant efficiency, the Sirio Centralized HV-MT and HHV-MT inverters do not have an integrated transformer. This feature and the meticulous design make them ideal for use in medium- high power plants connected to a medium voltage grid.

CHARACTERISTICS

Maximum energy and safety

The Maximum Power Point Tracking (MPPT) research algorithm implemented in the control system of Sirio Centralized inverters allows full use of the photovoltaic generator in any radiation and temperature conditions, making the plant work constantly at maximum efficiency. In the absence of solar radiation the converter goes on standby and resumes normal operation when there is radiation again. This feature reduces self-consumption to a minimum and maximizes energy efficiency. The use of speed-controlled fans helps to optimize the overall efficiency of the inverter. Fan operation that is linked to the temperature also increases the expected lifespan and reduces costs incurred for extraordinary maintenance. All these design features, the careful choice of components and guaranteed quality of production according to ISO9001 standards make the three-phase inverters Sirio Centralized extremely efficient and reliable and guarantee maximum energy production.

To guarantee greater safety standards and the prevention of fires in the event of an internal fault in the converter, the Sirio Centralized K330, K500 and K800 HHV-MT are equipped as standard with a DC side motorized disconnect switch equipped with a minimum voltage coil. Furthermore, the presence of 8, 8 and 16 inputs respectively, protected by fuses placed on both poles, guarantees the protection of the lines arriving from the field panels; this measure ensures that second level switchboards (DC-Boxes) are not foreseen in the design phase with a consequent economic saving. The operation of the fans linked to the temperature also allows them to increase their expected life by reducing the costs due to extraordinary maintenance.

All these design features, the careful choice of components and guaranteed quality of production according to ISO 9001 standards make the three-phase inverters Sirio Centralized extremely efficient and reliable and guarantee maximum energy production

Thermal derating

Derating as a function of temperature aimed to safeguard against overheating inverter semiconductors in the case of environments with temperatures exceeding installation specifications or for forced ventilation faults, without causing a complete block of the inverter itself. Sirio Centralized models ensure rated power output up to 45°C environment. If this threshold is exceeded, the inverter gradually decreases the power fed into the network in such a way as to maintain heat sink temperature within the maximum limit. Once back in the range of thermal normal operation, the inverter restores the optimal working point, again ensuring maximum power transfer.

Easy installation and maintenance

The footprint of these devices has been considerably reduced and there is no need to leave space at the side or back of the equipment since the electronics and power components are fully accessible from the front. Fully automatic operation ensures ease of use and facilitates installation and startup, thus avoiding installation and configuration errors which could lead to failures or reduced plant productivity.

User interface

The Centralized Sirio inverters feature a new user interface as standard consisting of a color LCD touch panel in a convenient 7'' format. The millions of colors and the number of possible functions greatly enrich the user's interaction experience with the solar inverter.

Intuitive icons and short messages in the set language guide the user through the simple menu structure, allowing access to all the inverter's consultation, configuration and command functions. In particular, it is possible to view the daily energy production graph and the instantaneous value of power produced, check the temperatures of the modules and the measurements of any analog probes installed.

The section dedicated to the archive allows the visualization and analysis of historical data by crossing measurements as desired (no more than two quantities at a time). By sliding your finger on the screen you can query the values recorded in previous days, even with monthly or annual intervals and the displayed graphs can be sent by email. The internal storage allows the archiving of approximately 5 years of data (it is however possible, if necessary, to delete older years using a specific function). The historical data produced by the inverter and that of the system board can be saved on a USB stick.

The device also allows you to change the €/kWh ratio, adjust the brightness of the display, change the system date and time, assign an identifier and a label to the system it belongs to, configure and customize up to 4 external analogue probes. It also allows the sending of e-mails (the periodicity of which can be set) with production data and graphs and, in the event of anomalies, any alarms due to failure or failed ignition.

Finally, in the Info section, using appropriate meters, it is possible to consult the total energy produced, the total hours of operation, the economic return of the system and other technical parameters, including the amount of memory used for historical data. The graphic interface is available in Italian, English, French, Spanish and German.

Access via network

If there is a local network connection, the touch screen device offers many communication possibilities. The inverter is compatible with both the proprietary PVSER protocol on the network and with ModBUS/TCP, thus offering easy insertion into any data management or analysis BMS that uses the Ethernet network.

The display software can be updated easily and in a very short time; furthermore, with freeware software (VNC) it is possible to remotely view the inverter screen on your computer or mobile device and interact with it.

Customized solutions

Riello Solartech is able on request to supply Sirio Centralized inverters specific to the client’s needs. Available options include the integrated isolation control and the pole/earth connection kit (positive or negative) that is required for some kinds of photovoltaic modules.