ndocs/bg/LOW VOLTAGE POWER DISTRIBUTION/Indirect protection devices/Surge arresters/SPD AC-DC type/%C4%E5%EA%EB%E0%F0%E0%F6%E8%FF%20%E7%E0%20%F1%FA%EE%F2%E2%E5%F2%F1%F2%E2%E8%E5%20-%20%C5%C4%CD%CE%CF%CE%CB%DE%D1%CD%C8%20%CA%C0%D2%CE%C4%CD%C8%20%CE%D2%C2%CE%C4%C8%D2%C5%CB%C8-%20SPD%20AC-DC.pdf