Analysis for Surge Immunity

CE is a safety certified standard, and it is regarded as the passport to enter into European Market. From the date of Jan.2, 2013, all the electric and electronic equipments export to European Market must be marked with CE, and for the CE test, EMC is a very important part of it. EMC test includes EMI test, electrostatic immunity test, fast transient immunity test, voltage dips, short interruptions and voltage variations immunity tests and surge immunity test. This article mainly discusses the lightning surge immunity test.

Test Method:
Surges are caused by over voltages from switching and lightning transients. And the purpose for surge immunity test is that build a common criterion to evaluate the performance of electric and electronic equipments suffer from surge shock. According to IEC 61000-4-5 Testing and Measurement Techniques – Surge immunity test, the surge generator should be simulation the waveform of 1.2/50us voltage wave, 8/20us current wave and combination wave (voltage wave: 10/700us; current wave: 5/320us), and then coupling the wave to tested circuit to achieve the experimental purpose. The test levels include class 1, class 2, class 3, class 4 and class X; among them, X is open level. And each level has its corresponding voltage strength, like table 1. And the test level depends on the environment and installation condition, classified as below:
Class 1: Partly protected electrical environment, like factory and control room of power station.
Class 2: Electrical environment where the cables are well-separated, even at short runs
Class 3: Electrical environment where cables run in parallel
Class 4: Electrical environment where the interconnections run as outdoor cables along with power cables, and cables are used for both electronic and electric circuits
Class X: Special conditions specified in the product specification

Table 1: Test Level

Level Open circuit test voltage±10%(KV)
1 0.5
2 1
3 2
4 4
X Special

Test Result:

Surge immunity test is a destructive test; the result can be divided according to the degree of damage:
a) Normal performance within limits specified by the manufacturer, requestor or purchaser;
b) Temporary loss of function or degradation of performance which ceases after the disturbance ceases, and from which the equipment under test recovers its normal performance, without operator intervention;
c) Temporary loss of function or degradation of performance, the correction of which requires operator intervention;
d) Loss of function or degradation of performance which is not recoverable, owing to damage to hardware or software, or loss of data.

Application Scope:
According to the newly EMC directive 2004/108/EC, Household Wireless and TVB, Mobile Radio Equipment, Medical and Science Equipment, Household Equipment, Electronic realia, R&TTE, Industrial Equipment, Mobile Wireless Equipment, ITE, Aeronautical and Maritime Mobile Radio, Communication Equipment and Lighting are requested to do the surge immunity test. See from the lighting industry, the surge immunity test should meet the following requirements (table 2) according to EN61547 Equipment for general lighting purposes EMC immunity requirements clause 5.7.

Table 2: Surges-Test levels at input AC power ports

Characteristics Test Level
Self-ballasted lamps Luminaires and independent auxiliaries
Input power
≤25W >25W
Wave-sharp data 1.2/50us 1.2/50us
Test Levels Line to Line ±0.5KV ±0.5KV ±1.0KV
Line to ground ±1.0KV ±1.0KV ±2.0KV

According to IEC61000-4-5,EN61000-4-5 and GB/T17626.5 standards, Lisun Group developed SG61000-5 surge generator, this equipment includes coupling and decoupling network (CDN), and with three models for optional:

Model SG61000-5 SG61000-5T SG61000-5H
Waveform 1.2/50us, 8/20us 1.2/50us, 8/20us 1.2/50us, 8/20us, 0/700us, 5/320us
Output Voltage 0-6KV±10% 0-6KV±10% 0-10KV±10%,0-6KV±10%
CDN 16A, single phase 20A, three phase 20A,three phase /30A, three phase

SG61000-5 surge generator is accepted by many electrical equipment manufacturers, like Capital Power Systems Ltd from India, SGS from Australia, World Testing Lab from Italy, TUV from German, Sharp from USA and etc. The reason why we can win so many trust and support from the world famous companies is because we always practice the motto right product, right price and right service. From the feedback, Lisun enjoy good reputation in the world market. And we will always provide the high quality products and superior service to all of our customers.