Application SP1-B series SPD is suitable for TT, IT, TN-S, TN-C-S power supply system with AC 50/60Hz, 230/400V and below. Its design based on IEC6143-1, GB18802.1 and GB50057 standard requirements, can discharge 100KA lightning over current, normally installed at incoming line of the main distribution box of buildings. B type lightning current SPD used for equipotential connection during lightning, installed at the LPZOA zone or junction area of LPZ1 zone, normally installed at the incoming line of low voltage main distribution board. Selection Principle ● Modularization - can replace the protection module without electricity cutoff. ● Big current - maximum can withstand 100KA(8/20µs) ● High speed - response time less than 25ns ● Status indication - the window color shows the working status : Green ( normal ), Red (fault)