Terminal blocks for photovoltaics

Although standard products can generally be used in the AC area of solar systems, a more specific approach is required for the DC area. In order to keep cable losses to a minimum, PV panels are connected to strings, thereby increasing the system voltage.
Off-load voltages of PV systems can be up to 1500 V DC.
These high DC voltages place particular demands on the components used. In contrast to AC voltage, the DC voltage that is present allows creepage distances to be created very easily on the surface of insulating elements. The components used in this area must therefore have increased air and creepage distances.
In order to limit reverse currents which can occur in the event of a short circuit, the individual strings are protected. This preferably takes the form of 10.3 x 38 mm fuses in crystalline modules and blocking diodes incorporated into the circuit in thin-film modules.

Terminal blocks and fuses from Phoenix Contact cleverly meet the special requirements of photovoltaic systems. You will find a summary of all components in the “Components and systems for photovoltaics” brochure.

Crystalline modules are characterized by a very high level of efficiency in good light conditions. These offer significantly higher string currents in comparison to the thin-film modules. The compact fuse terminal blocks protect PV cables against dangerous reverse currents.

Compared to crystalline modules, thin-film modules perform more favorably in weak light and are more sensitive to reverse currents. Block diodes connected in series are often used for fast and reliable protection in the case of reverse currents.