... -C,SP1-D,SP1-NPE,OBO Germany surge protective device,Power Suppressor,SPD,Surge Protective,Surge ,Lightning,ArresterPower Surge ... blocks Simple installation via the marked terminals. 4. Thermal isolating device with optical indication Permanent check of arrester serviceability. 5 ... surge arrester is damaged by overloading, the integral isolating device breaks the connection to the mains. This is ...