ISO9001 380V Surge Protection Metal Box Type With Warning Indicator
I. Overview
EPP series AC power supply lightning protector consists of several monolithic lightning protection chips, which can be freely combined into single-phase or three-phase protection for different power distribution systems to prevent damage to low-voltage power equipment from inductive overvoltage or operational overvoltage. epp80t is usually used for secondary protection.
Features
visual warning indicator, aging thermal decoupling and short circuit overcurrent decoupling, thermal backup, aging prediction, 35mm standard rail mounting, etc.
site conditions before installation
1,There is a reliable grounding system, and the grounding resistance is measured on the grounding stake (strip) of the distribution cabinet (SPD installation), and the resistance should meet the national standard.
2,Space should be left in the distribution cabinet for the installation of SPD.
Note: L is the fire wire, N is the zero wire, E is the ground wire.
Voltage spikes[edit]
In an AC circuit a voltage spike is a transient event, typically lasting 1 to 30 microseconds, that may reach over 1,000 volts. Lightning that hits a power line can give many thousands, sometimes 100,000 or more volts. A motor when switched off can generate a spike of 1,000 or more volts. Spikes can degrade wiring insulation and destroy electronic devices like light bulbs, battery chargers, modems and TVs etc.
Spikes can also occur on telephone and data lines when AC main lines accidentally connect to them or lightning hits them, or if the telephone and data lines travel near lines with a spike and the voltage is induced.
A long term surge, lasting seconds, minutes, or hours, caused by power transformer failures such as a lost neutral or other power company error, are not protected by transient protectors. Long term surges can destroy the protectors in an entire building or area. Even tens of milliseconds can be longer than a protector can handle. Long term surges may or may not be handled by fuses and overvoltage relays.
Surge currents[edit]
Surge Currents are much lower in Category A locations than at Category B and C locations.
Category A loads are more than 60 feet of wire length from the service entrance to the load. Category A loads can be exposed to 6kV, 0.5kA surge currents.
Category B loads are more than 30 feet from the service entrance and less than 60 feet of wire length from the service entrance to the load. Category B loads can be exposed to 6kV, 3kA surge currents.
Category C loads are less than 30 feet from the service entrance to the load. Category C loads can be exposed to 20kV, 10kA surge currents.[2]
A building's wiring adds impedance limits the surge current that reaches the loads. There is less surge current at longer wire distances and where more impedance is present between the service entrance and the load.[3]
A coiled extension cord can be used to increase the wire length to more than 60 feet and to increase the impedance between the service entrance and the load.[4]
