Solar Plant Supervisory System (SPSS) is a complete hardware and software solution for monitoring and control solar power plants. Measuring, comunication and control equipment is developed and manufactured by Robotina. Photovoltaic panels and inverters are selected from other manufacturers, providing the optimal solution for each plant.

We offer a turnkey solution for solar plants of all sizes, from smallest to largest. That includes project design, installation, comissioning and hosting services.

We also sell equipment individually. You choose panels and inverters, and connect them to our monitoring system. You may even combine with other manufacturers, e.g. use our string monitors with a controller from an other manufacturer.

main components of a photovoltaic plant


Plant with no monitor system produce electricity just as well, given that panels, inverters and connections are all in perfect shape. But, do they really are?

Trouble is, it's really hard to tell weather plant is giving the optimal output, just by looking at momentary power. A minute defect, a crack or piece of dirt, may reduce the total output significantly. That condition may stay unnoticed for years, loosing a pretty money.

Monitoring system provides optimal and predictable output, with a least possible downtime. Automatic reporting ensures quick repairs, reducing dropouts and increasing profit.

easy access to available measurements


  • on-line monitoring measurements and status signals
  • remote access and control using standard web browser
  • hosted locally or remotely on commercial hosting service
  • data-base storage for long-term access and analysis
  • simple one-click data export to spreadsheet program
  • immediate notification in case of operational failure
  • anti-theft alarm, access control and video surveillance


  • each fuse is individually monitored and has flashing LED indicator
  • string current is measured in both positive and negative leg, providing early failure detection
  • wide range of ordering options: plastic/inox housing, MC3/MC4/cage-clamps/faston connectors
  • spare inputs and outputs (4+4 for each string monitor) may be used for various custom functions
  • system own consumption is taken separately from the grid, not from photovoltaic cells
  • very low power consumption, one string monitor in active state draws only 1.2W
  • very high efficiency, string monitor internal power loss is 1.2W per string at 10A
  • less internal heating means longer maintenance intervals and product lifetime
  • different vendor equipment, such as inverters and power meters, may be integrated into system
  • server may be located within plant facility, or hosted remotely at user-selected hosting provider
  • designed to run on standard web hosting service, much cheaper then dedicated server
  • platform-independent software, written in Python, may run on Linux or Windows server
  • based on reliable and widely used open-source Apache/MySQL platform
  • integrated udp-hole-punching system allows easy controller-to-server connection

string monitor box functions and connections


  • SMB (string monitor box) - measures string currents, voltage and other parameters
  • SDB (string diode box) - serial diodes for protecting strings against reverse current
  • DCB (dc combiner box) - passive combiner box, joins power wires before inverter
  • PCS (photovoltaic inverter) - converts DC to AC current and feeds energy to power grid
  • PSU (power supply unit) - power supply and galvanic isolation for string monitors
  • SCU (solar controller unit) - communication controller, keeps track of measurements and alarms

connection diagram of photovoltaic plant


  • Solar Web - full-featured multi-platform monitoring and control system, local or remote
  • Solar Mini - simple local scada for quick preview, presentations and custom solutions
  • Solar Scope - set of software tools for easy comissioning and meticulous error detection
  • OPC Server - communication driver for connecting solar controller to scada from other vendors

solar controller panel