PV Protection
INTRODUCTION
®
Altech Corp. provides high-quality solutions for the complete overcurrent
and overvoltage protection of applications in the field of photovoltaic and
other renewable energy sources. Our products are designed for complete
protection of:
• DC circuits (overvoltage protection and reverse current protection)
• Circuits inside DC/AC inverters (semiconductor protection)
• AC circuits between the inverter and the power grid
(overvoltage, overcurrent and anti-islanding protection).
The products are internationally certified and carry several quality marks.
DC - DISTRIBUTION AND PROTECTION COMPONENTS
Photovoltaic systems are composed by photovoltaic panels, cables, fuses, switches, overvoltage arresters and
power inverter. Photovoltaic panels utilise the power of sun light to converters photons to DC current.
Electricity generated by solar panels is then fed into a power inverter that converts DC current to AC current. gPV
fuse has been developed to protect cable and panel against "reverse" overcurrent.
Overcurrent Protection
PV module protection from DC REVERSE current on DC side Array with three or more strings of panels. PV systems
that have three or more strings connected in parallel need to have the positive string protected by fuses. Systems
that have less than three strings will not generate enought fault current to damage the conductors/solar panels.
Normaly in North America there is a gPV fuse connected on the positive string, that protect conductors/solar panels
from damage and eliminate any safety hazards. Fuses isolate the faulted string. The rest of PV system can continue
to generate electricity.
PV module protection from AC REVERSE current caused by defective inverter If an inverter becomes defective
(transformerless…), AC reverse current can feed into DC strings and destroy PV modules.
Altech Corp.® • 35 Royal Road • Flemington, NJ 08822-6000 • 908.806.9400 • 908.806.9490 (fax) • www.altechcorp.com
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