The ZGG40-1000 (3) z Modular Power Supply SPD consists of three ZGG40-500MK power supply modules and an integration base in «Y Connection», with a full protection mode of L (+)/N (-) -PE and L (+) - N (-). used for secondary and tertiary protection of the AC/DC system L(+)-N(-) and L(+)/N(-)-PE. The modules are equipped with the anti-reverse slot design, overtemperature protection, failure indication and remote signalling alarm dry contact, through which the installation and working status of modules can be monitored to see if reliable. Applied to the low voltage AC/DC power distribution system, the SPD is connected between AC/DC power supply and system equipment in parallel, preventing equipment from the impulse surge and transient overvoltage caused by the outside environment (such as lightning, EMI, etc.) or by the system (such as switching effects of the system, startup or shutoff of the inductance and capacitance load, etc.).