1. EET 422 EMC & COMPLIANCE ENGINEERING
Prof R T Kennedy
EMC & COMPLIANCE ENGINEERING

2. EN 61000-3-12 APPLICABLE TO electrical and electronic equipment
connected to the public low voltage
(230 V, 50 Hz) ac distribution system
CURRENT LEVELS per phase
16 A < CURRENT  75 A
Prof R T Kennedy
EMC & COMPLIANCE ENGINEERING

3. simplified connection
MEASURE
1.5s smoothed harmonics
& averages
3 - STAGE
ASSESSMENT PROCESS
CALCULATE
THD PWHD % IH
< stage 1 limits
YES
simplified connection NO
< stage 2 limits
YES
connect
specify RSCE min NO
REQUEST SUPPLY AUTHORITY
Prof R T Kennedy
EMC & COMPLIANCE ENGINEERING

4. EMC & COMPLIANCE ENGINEERING
THD: TOTAL HARMONIC DISTORTION
PWHD: PARTIAL WEIGHTED HARMONIC DISTORTION
the rms values of a group of higher harmonics
ratio
fundamental rms
to reduce the effect of the higher harmonics
Prof R T Kennedy
EMC & COMPLIANCE ENGINEERING

5. EMC & COMPLIANCE ENGINEERING
RSCE NOT RESISTANCE
R = RATIO
R = SHORT CIRCUIT RATIO
Prof R T Kennedy
EMC & COMPLIANCE ENGINEERING

6. STAGE 1: % HARMONIC CURRENT
STAGE 1 LIMITS
STAGE 1: % HARMONIC CURRENT % 2 3 4 5 6 7 8 9 10 11 12 13
THD
PWHD
21.6
10.7
1.3
7.2 1
3.8
0.8
3.1
0.7 23
Prof R T Kennedy
EMC & COMPLIANCE ENGINEERING

7. EMC & COMPLIANCE ENGINEERING
STAGE 2 LIMITS
BALANCED 3-PHASE
STAGE 2:
BALANCED 3-PHASE
% HARMONIC CURRENT %
RSCE min 2 4 5 6 7 8 10 11 12 13
THD
PWHD 33
10.7
2.7
7.2
1.6
3.1
1.3 22 66 14 9 3 16 25
120 19 28
250 31 20 37 38
≥ 350 40 15 48 45
SPECIFY RSCEmin
SUPPLY AUTHORITY VERIFICATION
Prof R T Kennedy
EMC & COMPLIANCE ENGINEERING

8. EMC & COMPLIANCE ENGINEERING
STAGE 2 LIMITS
BALANCED 3-PHASE
special conditions
STAGE 2: BALANCED 3-PHASE
SPECIAL OPERATING CONDITIONS
% HARMONIC CURRENT %
RSCE min 2 4 5 6 7 8 1 11 12 13
THD
PWHD 33
10.7
2.7
7.2
1.6
3.1
1.3 22
≥ 120 40 25 15 10 48 45
SPECIFY RSCEmin
SUPPLY AUTHORITY VERIFICATION
Prof R T Kennedy
EMC & COMPLIANCE ENGINEERING

9. EMC & COMPLIANCE ENGINEERING
STAGE 2 LIMITS
BALANCED 3-PHASE
special conditions
uncontrolled bridge rectifier + capacitor
fully controlled bridges
5th and 7th harmonic currents < 5% of fundamental
12 pulse converters
Prof R T Kennedy
EMC & COMPLIANCE ENGINEERING

10. EN61000-3-12 UN-BALANCED 3-PHASE STAGE 2 LIMITS
STAGE 2: UN-BALANCED 3-PHASE % HARMONIC CURRENT
STAGE 2: UN-BALANCED 3-PHASE % HARMONIC CURRENT
STAGE 2: UN-BALANCED 3-PHASE % HARMONIC CURRENT Q
APPENDIX 10
EXAM #
YEAR 6
TO BE SUBMITTED WITH SCRIPT
2008 Q
APPENDIX 10
EXAM #
YEAR 6
TO BE SUBMITTED WITH SCRIPT
2008 Q
APPENDIX 10
EXAM #
YEAR 6
TO BE SUBMITTED WITH SCRIPT
2008
TABLE 4
TABLE 4
TABLE 4 EN
STAGE 2 LIMITS
UN-BALANCED 3-PHASE
STAGE 2: UN-BALANCED 3-PHASE
% HARMONIC CURRENT %
RSCE min 2 3 4 5 6 7 8 9 10 11 12 13
THD
PWHD 33
21.6
10.7
2.7
7.2
3.8
1.6
3.1
1.3 20 23 66 24 26
120 27 15 30
250 35 40
≥ 350 41 47
ESTIMATE HARMONIC VOLTAGES
based on source impedance
STATEMENT
Prof R T Kennedy
EMC & COMPLIANCE ENGINEERING

11. supply authority acceptance for connection to
STAGE 2: UN-BALANCED 3-PHASE % HARMONIC CURRENT
STAGE 2: UN-BALANCED 3-PHASE % HARMONIC CURRENT
STAGE 2: UN-BALANCED 3-PHASE % HARMONIC CURRENT Q
APPENDIX 10
EXAM #
YEAR 6
TO BE SUBMITTED WITH SCRIPT
2008 Q
APPENDIX 10
EXAM #
YEAR 6
TO BE SUBMITTED WITH SCRIPT
2008 Q
APPENDIX 10
EXAM #
YEAR 6
TO BE SUBMITTED WITH SCRIPT
2008
TABLE 4
TABLE 4
TABLE 4
"this equipment
requires
supply authority acceptance
for connection to
the public supply networks" EN
STAGE 2 LIMITS
UN-BALANCED 3-PHASE
STATEMENT
Prof R T Kennedy
EMC & COMPLIANCE ENGINEERING

12. supply authority acceptance for connection to
"this equipment
requires
supply authority acceptance
for connection to
the public supply networks"
Prof R T Kennedy
EMC & COMPLIANCE ENGINEERING

13. FORMULAE for CALCULATIONS
Prof R T Kennedy
EMC & COMPLIANCE ENGINEERING

14. EMC & COMPLIANCE ENGINEERING
Prof R T Kennedy
EMC & COMPLIANCE ENGINEERING

15. EMC & COMPLIANCE ENGINEERING
THE REST IS SILENCE
NO 'MORE' EMI
Prof R T Kennedy
EMC & COMPLIANCE ENGINEERING