Omrdon Technology 
1, lightning protection zone (lightning protection zone) (LPZ): the division of the electromagnetic environment of lightning strikes, a lightning protection zone interface does not necessarily have to have a physical interface, for example, does not necessarily have to have walls, floors or ceilings as the zone interface.
2, lightning electromagnetic impulse (lightning electromagnetic impulse) (LEMP): lightning flow through the resistance, inductance, capacitance coupling electromagnetic effect, including lightning surge and radiation electromagnetic field. 2.0.26 electrical systemelectrical system by the low-voltage power supply combination of components constitute the system. Also called low-voltage power distribution system or low-voltage power distribution lines.
3, electronic system (electronic system) by the sensitive electronic components of the system.
4, building (structure) within the system internal system building (structure) within the electrical system and electronic system.
5, surge protective device (SPD) used to limit transient overvoltage and discharge surge current device. It contains at least one nonlinear element.
6, the protection mode modes of protection electrical system surge protector protection components can be connected to the relative phase, relative ground, relative neutral line, neutral line to ground and its combination, as well as electronic system surge protector protection components connected to the line and line, line and ground and its combination.
7, the maximum continuous operating voltage maximum continuous operating voltage (Ue) can be continuously added to the electrical system surge protector protection mode of the maximum square root voltage or DC voltage; can be continuously added to the electronic system surge protector terminals, and does not cause the transmission characteristics of the surge protector to reduce the maximum square root voltage or DC voltage.
8, nominal discharge current nominal discharge current (In) flow through the surge protector 8/20μs current wave peak.
9, impulse current impulse current (Iimp) by the current amplitude Ipeak, charge Q and unit energy W / R limited.
10, to Iimp test surge protector SPD tested with Iimp withstand 10/350μs typical waveform of part of the lightning current surge protector needs to use Iimp current to do the corresponding impact test. Class I test class I test electrical system using class I test surge protector with nominal discharge current In, 1.2/50μs surge voltage and the maximum surge current Iimp test. Class I test can also be used T1 plus box, that is, T1, In test surge protector SPD tested with In withstand 8/20μs typical waveform of the induced inrush current surge protector needs to use In current to do the corresponding impact test.
11, class II testclass II test electrical system with a class II test surge protector to use the nominal discharge current In, 1.2/50μs inrush voltage and 8/20μs current wave maximum discharge current Imax to do the test. Class Ⅱ test can also be used T2 plus the box indicates that the surge protector SPD tested with a combinationwave withstand 8/20μs typical waveform of the inductive surge current surge protector needs to be Isc short-circuit current to do the corresponding impact test.
12, class III test class III test electrical system using the I test surge protector to use a combination of waves to do the test. Combined wave is defined as a 2Q combined wave generator to produce 1.2/50μs open-circuit voltage Uoc and 8/20μs short-circuit current Isc. class II test can also be used to T3 plus box, that is, T3.
13, voltage switching type surge protector voltage switching type SPD no surge occurs when the high impedance, when there is a voltage surge when the sudden change to low impedance. Usually used discharge gap, inflatable discharge tube, silicon controlled rectifier or triac components to do this type of surge protector components. Also known as “Crobar type“ surge protector. With discontinuous voltage and current characteristics.
14, voltage limiting type surge protector voltage limiting type SPD no surge appears as high impedance, with the increase of surge current and voltage, the impedance continuously becomes smaller. Usually used varistors, suppressor diodes do voltage limiting type surge protector components. Also known as the “dominant voltage type” surge protector. Has continuous voltage and current characteristics.
15、Combination type surge protectorcombination type SPD by the voltage switching components and voltage-limiting components combined into a surge protector, its characteristics with the characteristics of the applied voltage can be expressed as voltage switching, voltage-limiting or voltage switching and voltage-limiting are available.
16、Measured limiting voltagemeasured limiting voltage applied to the specified waveform and amplitude of the shock wave, in the surge protector terminals asked to measure the maximum voltage value.
17, voltage protection level voltage protection level (Up) characterizes the surge protector to limit the terminals to ask the performance parameters of the voltage, the value can be selected from a list of priority values. Voltage protection level value should be greater than the highest value of the measured limit voltage.
18, 1.2/50μs voltage impulse 1.2/50μsvoltage impulse specified wave head time T1 for 1.2μs, half-value time T2 for 50μs of the impulse voltage.
19、8/20μs inrush current8/20μscurrent impulse stipulates that the wave head time T1 is 8 μs, and the half-value time T2 is 20 μs of the inrush current.
20, equipment impulse withstand voltage rating rated impulse withstand voltage ofequipment (Uw) equipment manufacturer to give the equipment impulse withstand voltage rating, characterizing its insulation against overvoltage tolerance.
21, insertion loss insertion loss in the electrical system: at a given frequency, connected to a given power supply system surge protector insertion loss for the power line immediately after the surge protector access point, in the test before and after the surge protector access to the voltage ratio, the results expressed in dB. Electronic system, due to the insertion of a surge protector in the transmission system caused by the loss, it is in the surge protector before the insertion of the power transferred to the back of the system part of the ratio of the power and surge protector insertion after the power transferred to the same part. It is usually expressed in dB.
22. return loss return loss reflection coefficient of the inverse mode. Generally expressed in decibels (dB).
23. near-end crosstalk (NEXT) Crosstalk is transmitted in the disturbed channel in a direction opposite to the direction of current transmission in the channel generating the disturbance. Near-end crosstalk is generated in the disturbed channel at a port that is usually close to, or coincides with, the supply side of the channel generating the disturbance.