In an electrical systems, Solar DC SPDs are usually installed in tap-off configuration (in parallel) between the live conductors and the earth. The operating principle of Solar DC SPD can be similar to that of a circuit breaker.
In normal use (no overvoltage): the Solar DC SPD is similar to an open circuit breaker. When there is an overvoltage: the Solar DC SPD becomes active and discharges the lightning current to earth. It can be likened to the closing of a circuit breaker which would short-circuit the electrical network with the earth via the equipotential earthing system and the exposed conductive parts for a very brief instant, limited to the duration of the overvoltage.
For the user, the operation of the Solar DC SPD is totally transparent as it only lasts a tiny fraction of a second.
When the overvoltage has been discharged, the Solar DC SPD automatically returns to its normal state (circuit breaker open).
|DC SPD in Solar Series
|UCPV (V DC)
|Max System Discharge Current (8/20 μs) [Imax]
|Voltage Protection Level [UP]
|Voltage Protection Level at 5kA [UP]
|Integrated Fuse Breaking Capacity/Interrupting Rating
|Short-Circuit Interruption (SCI) Overcurrent Protection
|Operating Temperature Range [TU]
|-40°C to +80°C
|Nominal Discharge Current (8/20 μs) [(DC+/DC-) --> PE] [n]
|Response Time [tA]
|Operating State/Fault Indication
|Green (good)/Red (replace)
|Conductor Ratings and Cross-Sectional Area
|60/75°C 1.5mm2/14AWG Solid/Flexible
|60/75°C 35mm/2AWG Stranded/25mm2/4AWG Flexible
|35mm DIN Rail per EN 60715
|UL 94V0 Thermoplastic
|Degree of Protection
|3 Modules, DIN 43880
|IEC 61643-31 Type 2, IEC 61643-1 Class II