Solar Surge Protection
Protect key system components like PV array, Micro-Inverter, Charger Controller, Inverter, Batteries.
The effects of lightning on a solar field, solar panels or their connected systems are destructive to say the least. PV components are often exposed and installed in locations not easily accessible making the need for surge protection even more critical. When lightning strikes a PV system it causes induced transient voltage spikes and current flow in the electrical wiring that can destroy equipment and damage terminal connections. Personal safety is of great concern as well since typical installations are used to power equipment being operated. To prevent these high energy surges from causing damage to the PV system the voltage surge must have a path of least resistance to redirect or dissipate through. All conductive surfaces should be directly grounded and all wiring that enters or exits a building or system component should be coupled through a surge protector.
Specifications Needed To Select Proper SPD
- The lightning round flash density
- The system’s operating temperature
- The system voltage
- System short circuit current rating (Imax)
- Systems maximum open circuit voltage (Voc)
- Level of protection direct vs. indirect
- Nominal system voltage (Vnom)
- Nominal system current (Iavg)
- Indoor vs outdoor installation
- SPD model Type 1 vs Type 2
- Surge detection and reaction speed
- Grounded vs isolated surge protection
DC Side Surge Protection
PV sources have very different current and voltage characteristics than traditional dc sources: they have a non-linear characteristic and cause long-term
persistence of ignited arcs. Therefore, PV current sources not only require larger PV switches and PV fuses, but also a disconnector for the surge protective
device which is adapted to this unique nature and capable of coping with PV currents. SPDs installed on the dc side must always be specifically designed for dc applications. The use of an
SPD on the incorrect ac or dc side is hazardous under fault conditions.
When SPDs are used on the dc side, they must also be used on the ac side due to the potential differences.
AC Side Surge Protection
Surge protection is just as important for the ac side as it is for the dc side. Ensure that the SPD is specifically designed for the ac side. For optimal protection, the SPD should be sized specifically for the system. The proper selection will guarantee the best protection with the longest lifespan.
On the ac side, multiple inverters can be connected to the same SPD if they share the same grid connection.