Elec­tro­mag­netic com­pat­i­bil­ity test­ing in EMC lab

EN 6100044:2012 Elec­tro­mag­netic com­pat­i­bil­ity (EMC) — Part 44: Test­ing and mea­sure­ment tech­niques — Elec­tri­cal fast transient/​burst immu­nity test (IEC 610004-4:2012)


Ana­log: IEC 610004-4:2012 Elec­tro­mag­netic com­pat­i­bil­ity (EMC) — Part 44: Test­ing and mea­sure­ment tech­niques — Elec­tri­cal fast transient/​burst immu­nity test.

Replace: EN 610004-4:2004 + A1:2010 Elec­tro­mag­netic com­pat­i­bil­ity (EMC) — Part 44: Test­ing and mea­sure­ment tech­niques — Elec­tri­cal fast transient/​burst immu­nity test.

New in this edi­tion: This edi­tion improves and clar­i­fies EFT sim­u­la­tor spec­i­fi­ca­tions, test cri­te­ria and test setups.

Scope
Inter­na­tional stan­dard EN 610004-4:2012 defines immu­nity require­ments for elec­tri­cal and elec­tronic equip­ment to repet­i­tive elec­tri­cal fast tran­sients on power sup­ply, sig­nal, con­trol and earth ports. This stan­dard defines test lev­els, test pro­ce­dures and var­i­ous test setups. This stan­dard does not define Pass/​Fail cri­te­ria, there­fore it must be used together with generic and spe­cific prod­uct stan­dards where prod­uct require­ments are stated.

Inter­na­tional stan­dard EN 610004-4:2012 defines:

  • Test volt­age waveforms;
  • Test lev­els;
  • Cal­i­bra­tion procedures;
  • Ver­i­fi­ca­tion procedures;
  • Spec­i­fi­ca­tions for lab­o­ra­tory and in situ tests.

Gen­eral
Induc­tive loads such as relays, switch con­tac­tors, or heavy-​duty motors when de-​energized pro­duce bursts of nar­row high– fre­quency tran­sients on the power dis­tri­b­u­tion sys­tem. These fast tran­sients can also be pro­duced when the util­ity provider switches in or out the power fac­tor cor­rec­tion equip­ment. A com­mon cause of power line tran­sients is spark­ing that occurs when­ever an AC power cord is plugged in, equip­ment is switched off, or when cir­cuit break­ers are opened or closed. The EN 610004-4:2012 spec­i­fi­ca­tion defines the test volt­age wave­form that is intended to sim­u­late the tran­sients cre­ated by switch­ing of induc­tive loads on AC power lines.

Test level
Inter­na­tional stan­dard EN 610004-4:2012 defines fol­low­ing pre­ferred test lev­els for var­i­ous ports:

EN61000-4-4 2012

Test­ing level must be selected accord­ing to generic and spe­cific prod­uct stan­dards. Cur­rent stan­dard also char­ac­terises var­i­ous envi­ron­ments and rec­om­mended test lev­els. For power ports immu­nity level is twice higher than for sig­nal and com­mu­ni­ca­tion ports.

Level 1: Well-​protected envi­ron­ment
Envi­ron­ment is char­ac­ter­ized as:
• sup­pres­sion of EFT in the switched power sup­ply and con­trol cir­cuits;
• sep­a­ra­tion between power sup­ply lines (a.c. and d.c.) and con­trol and mea­sure­ment cir­cuits com­ing from other envi­ron­ments belong­ing to higher sever­ity lev­els;
• shielded power sup­ply cables with the screens earthed at both ends on the ref­er­ence ground of the instal­la­tion, and power sup­ply pro­tec­tion by fil­ter­ing.
A server room, sen­si­tive lab­o­ra­tory room may rep­re­sent this environment.

Level 2: Pro­tected envi­ron­ment
Envi­ron­ment is char­ac­ter­ized as:
• par­tial sup­pres­sion of EFT in the power sup­ply and con­trol cir­cuits which are switched only by relays (no con­tac­tors);
• poor sep­a­ra­tion of the indus­trial cir­cuits belong­ing to the indus­trial envi­ron­ment from other cir­cuits asso­ci­ated with envi­ron­ments of higher sever­ity lev­els;
• phys­i­cal sep­a­ra­tion of unshielded power sup­ply and con­trol cables from sig­nal and com­mu­ni­ca­tion cables.
The con­trol room in EMC lab­o­ra­tory may rep­re­sent this environment.

Level 3: Typ­i­cal indus­trial envi­ron­ment
Envi­ron­ment is char­ac­ter­ized as:
• no sup­pres­sion of EFT in the power sup­ply and con­trol cir­cuits which are switched only by relays (no con­tac­tors);
• poor sep­a­ra­tion of the indus­trial cir­cuits from other cir­cuits asso­ci­ated with envi­ron­ments of higher sever­ity lev­els;
• poor sep­a­ra­tion power sup­ply, con­trol and telecom­mu­ni­ca­tion lines;
• earth rep­re­sented by con­duc­tive pipes, earth con­duc­tors in the cable trays (con­nected to the pro­tec­tive earth sys­tem) and by a ground mesh.
Indus­trial loca­tion with assem­bly lines may rep­re­sent this environment.

Level 4: Severe indus­trial envi­ron­ment
Envi­ron­ment is char­ac­ter­ized as:
• no sup­pres­sion of EFT in the power sup­ply and con­trol and power cir­cuits which are switched by relays and con­tac­tors;
• no sep­a­ra­tion of the indus­trial cir­cuits belong­ing to the severe indus­trial envi­ron­ment from other cir­cuits asso­ci­ated with envi­ron­ments of higher sever­ity lev­els;
• no sep­a­ra­tion between power sup­ply, con­trol, sig­nal and com­mu­ni­ca­tion cables;

Power plants may rep­re­sent this environment.

Appli­ca­tion of EFT pulses
Pri­mar­ily, the test­ing involves injec­tion of EFT pulses into the equipment’s AC power sup­ply lines. The EFT wave­form can also be injected into the sig­nal and con­trol lines, and earth con­nec­tions to sim­u­late the cou­pling of tran­sient noise onto these lines. The pulse wave­form has a high ampli­tude, short rise time, high rep­e­ti­tion rate and a low energy con­tent. It con­sists of a burst of 75 pulses repeated every 300 mil­lisec­onds for a dura­tion of 1 minute. Both pos­i­tive and neg­a­tive polar­ity EFT pulses are injected dur­ing testing.

EN61000-4-4 2012 1

EUT is located on non-​metallic table 10cm above hor­i­zon­tal ground plane on insu­la­tion sup­port. Hor­i­zon­tal ground plane is bonded to ground­ing sys­tem as well as test gen­er­a­tor and cou­pling decou­pling net­work. The equip­ment under test shall be arranged and con­nected to sat­isfy its func­tional require­ments, accord­ing to the equip­ment instal­la­tion specifications.

EN61000-4-4 2012 2

Direct cou­pling of EFT volt­age on power ports, using coupling/​decoupling net­work, is pre­ferred. For equip­ment under test hav­ing a power port with no earth ter­mi­nal, the test volt­age is only applied to L and N lines. If a suit­able cou­pling decou­pling net­work is not avail­able, one of alter­na­tive meth­ods can be used:
• in case of com­mon and un-​symmetric modes, direct injec­tion using the (33 ± 6,6)nF capac­i­tors is the pre­ferred cou­pling mode;
• if direct injec­tion is not prac­ti­cal, the capac­i­tive clamp shall be used.

For sig­nal, con­trol and telecom­mu­ni­ca­tion ports capac­i­tive cou­pling clamp is used. For earth ter­mi­nals cou­pling decou­pling device is preffered.

Per­for­mance cri­te­rion
The tests results are clas­si­fied in terms of loss of func­tion or degra­da­tion of per­for­mance. Inter­na­tional stan­dard EN 610004-4:2012 does not define Pass/​Fail cri­te­ria. This is defined by generic or spe­cific prod­uct stan­dards. EN 610004-4:2012 defines per­for­mance cri­te­ria that can be used to eval­u­ate equip­ment under test performance.

Per­for­mance cri­te­rion A
Nor­mal per­for­mance within lim­its spec­i­fied by the manufacturer;

Per­for­mance cri­te­rion B
Tem­po­rary loss of func­tion or degra­da­tion of per­for­mance. Self-​recovery after the test, with­out oper­a­tor intervention;

Per­for­mance cri­te­rion C
Tem­po­rary loss of func­tion or degra­da­tion of per­for­mance. Oper­a­tor inter­ven­tion needed for recov­ery after the test;

Per­for­mance cri­te­rion D
Loss of func­tion or degra­da­tion of per­for­mance which is not recov­er­able. Dam­age
of hard­ware or soft­ware, or loss of data.

The manufacturer’s spec­i­fi­ca­tion may define effects on the EUT which may be con­sid­ered insignif­i­cant, and there­fore acceptable.

eXTReMe Tracker