According to statistics, 70% of the damage caused by lightning is from lightning propagating along the power supply line and on the signal line. Therefore, in order to limit the damage caused by lightning transmission, it is necessary to coordinate the use of lightning cutting and filtering systems.
Lightning arresters and filters must be installed on all power supply lines in the power network to be protected. Lightning arresters are used to cut off most of the lightning energy transmitted to the ground and reduce the amplitude of lightning impulses. At the same time, lightning filters reduce the amplitude of lightning impulses and, at the same time, the rate of lightning current and voltage variations.
a) Protection against lightning along the power supply line
+ Thiết bị cắt sét
– Lightning arresters are installed in parallel with the equipment protection system.
– Meet the standards of the lightning protection industry in particular and the electricity industry in general.
– Using the most advanced technology today, allowing to withstand large lightning current, fast impact time, low residual voltage (throughput voltage), continuous work on the grid, not isolated. from the network when a transient overvoltage occurs like traditional MOV technology.
– Capable of reducing large surge currents
– Capable of multi-pulse cutting.
– Capable of distinguishing lightning impulse and overvoltage of the grid according to the frequency principle, suitable for power networks in Southeast Asia with poor quality of voltage stability due to the ability to distinguish abnormal overvoltages on the road. wire and overvoltage due to lightning impulse.
– LED warning light system, remote contact allows monitoring and monitoring the working status of the device.
– Installation and operation conditions are simpler.
– It has a compact size and a sealed metal shell that is safe for people and devices.
+ Thiết bị cắt lọc sét
– Installed in series with the equipment to be protected.
– The device is made with 3 layers of protection: Lightning + Lightning filter + Lightning cut-off
— Lightning impulse energy is suppressed to ground and neutral via phase-to-neutral (L-N) and neutral-earth (N-E) circuits in the primary lightning cut-off stage.
— Filter stage: use L-C low-pass filter circuit to filter lightning, filter pulse noise affecting the power supply line
— Secondary lightning cutting stage: secondary protection of the phase-neutral circuit (L-N) to filter out the remaining voltage spikes after passing the first two layers of protection to provide a safe output power for the load.
– Low residual voltage
– Has all the advantages of surge arresters.
– Filter and attenuate noise, ensuring complete suppression of spikes. Reduces the voltage variation rate (dv/dt) and current rate variation (di/dt) of the lightning current.
b) Lightning protection on signal lines
Lightning protection devices on signal lines usually focus on protecting LAN devices, transmission ports, signal cables, control cables, etc.