If there is no direct lightning protection, according to the estimation of iec1312, almost all lightning currents flow through the conductor lines (power line, signal line, etc.) in and out of the building, and such damage is very serious. Therefore, good direct lightning protection is the premise of inductive lightning protection; Direct lightning protection is designed and constructed in accordance with the national standard gb50057 code for design of lightning protection of buildings. It mainly uses lightning rod, network, wire, belt and good grounding system. Its purpose is to protect the building from lightning and provide a relatively safe environmental weak current for people or equipment in the building.

The statistical data of monitoring engineering show that more than 80% of lightning accidents in microelectronic network system are caused by lightning impulse overvoltage induced on the power line connected to the system. Therefore, the protection of power line is a link that can not be ignored in the overall lightning protection.

Although lightning protection devices are installed on external incoming lines such as power supply and communication lines, the overvoltage induced by lightning on network lines (such as twisted pair) will still affect the normal operation of the network and even damage the network system. A huge transient magnetic field is generated when lightning strikes. Metal loops within 1km, such as network metal wires, will sense extremely strong induced lightning strikes.

The central machine room where the backbone switch of the integrated network system is located shall be provided with a grading ring to electrically connect all metal objects in the machine room, including cable shielding layer, metal pipes, metal doors and windows, equipment shell and all metal pipes in and out of the building, and connect them to the grading ring to balance the potential weak current.

The production of lightning protection grounding grid is the guarantee for the effective function of lightning rod, lightning strip, lightning arrester and other facilities.

Lightning protection scheme.

No1. Lightning protection and overvoltage protection of power supply system.

Since the power supply of your computer room is introduced from the main power distribution of the building. The lightning protection at the high voltage end of the power supply has been implemented by the power supply department. Therefore, for the lightning protection of UPS power supply system, we adopt the following lightning protection scheme:.

NO2. Lightning protection of UPS power supply system.

Two level input lightning protection shall be provided for the special distribution cabinet and UPS power supply in the machine room. The specific protective measures are:.

Class I protection: install three-phase power supply lightning arrester (single-phase power supply lightning arrester) in front of the power distribution cabinet in the machine room.

Level II protection: install three-phase power supply lightning arrester (single-phase power supply lightning arrester) in front of UPS power supply.

Level III Protection: install power lightning protection sockets at important equipment.

No3. Lightning protection and overvoltage protection of communication system.

Lightning protection of communication system includes communication lines from outdoor to indoor, mainly including network communication lines, special lines, microwave communication lines (antenna feeder), video lines, etc; According to the situation of the machine room provided by you, the signal lines may be transmitted by optical fiber, so it can not be protected, but both ends of the optical fiber shall be grounded. If there is an optical transceiver, the optical transceiver shall be protected. If optical fiber is not selected, lightning arrester and weak current shall be selected according to the type of signal line.

No4. Installation and wiring.

a. The function of lightning arrester is to absorb and discharge lightning current. All lightning protection products must be grounded.

b. The lightning arrester is connected in series / parallel between the protected equipment and the signal channel;.

c. The input end (in) of the signal lightning arrester is connected with the signal channel, and the output end (out) is connected with the protected equipment and installed close to the protected equipment, which cannot be reversed; weak current.

d. The grounding wire of the lightning arrester shall be reliably connected with the grounding bar of the lightning protection system. The shorter the wiring, the better, and the length shall not exceed 1m.