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SUSCEPTIBILITY (IMMUNITY)

SUSCEPTIBILITY (IMMUNITY). Radiated - RF (Radio or High Frequency) Electric and Low Frequency Magnetic Fields Conducted - Voltage Pulses of varying duration and energies including electrostatic voltage Conducted - RF Voltage (high frequency voltage) Conducted - Unstable AC power source.

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SUSCEPTIBILITY (IMMUNITY)

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  1. SUSCEPTIBILITY(IMMUNITY) • Radiated - RF (Radio or High Frequency) Electric and Low Frequency Magnetic Fields • Conducted - Voltage Pulses of varying duration and energies including electrostatic voltage • Conducted - RF Voltage (high frequency voltage) • Conducted - Unstable AC power source J. Kautzer

  2. SUSCEPTIBILITY(IMMUNITY) Response ?? • Product Response Summary per (EN61000-6-2): • Level (A) 1: No discernable change in product operation and function • Level (B) 2: Safe effect is noted in the product operation or function. Effect disappears when stress is removed without intervention. • Level (C) 3: Safe effect is noted in the product operation or function. Effect requires operator intervention to completely recover after stress is removed. • Level (D) 4: Safe effect is noted in the product operation or function. Effect requires service intervention to completely recover when stress is removed. (Repair) J. Kautzer

  3. SUSCEPTIBILITY(IMMUNITY) Criteria A • Product Response Detail per (EN61000-6-2): • Criteria A (Level 1): “The apparatus shall continue to operate as intended DURING and AFTER the test. No degradation of performance or loss of function is allowed below a performance level specified by the Mfg when the apparatus is used as intended. The performance level may be replaced by a permissible loss of performance. If the minimum performance level or the permissible loss is NOT specified by the Mfg, either of these may be derived from the product description and documentation, and from what the user may reasonably expect from the apparatus if used as intended.” J. Kautzer

  4. SUSCEPTIBILITY(IMMUNITY) Criteria B • Product Response Detail per (EN61000-6-2): • Criteria B (Level 2): “The apparatus shall continue to operate as intended AFTER the test. No degradation of performance or loss of function is allowed below a performance level specified by the Mfg when the apparatus is used as intended. The performance level may be replaced by a permissible loss of performance. During the test, degradation of performance is however allowed. No change of actual operating state or stored data is allowed. If the minimum performance level or the permissible loss is NOT specified by the Mfg, either of these may be derived from the product description and documentation, and from what the user may reasonably expect from the apparatus if used as intended.” J. Kautzer

  5. SUSCEPTIBILITY(IMMUNITY) Criteria C • Product Response Detail per (EN61000-6-2): • Criteria C (Level 3): “Temporary loss of function is allowed, provided the function is self-recoverable or can be restored by the operation of the controls.” J. Kautzer

  6. SUSCEPTIBILITY(IMMUNITY) • Any response other than Level 1 requires that response/mode warning to be disclosed in operator /service manual • Governed by many different IEC test standards in the IEC61000-4 series • Most good product designs require Level 1 or 2 responses although many products fail to meet it and are inadequately informing the user • Any unsafe response to any of the series of tests is not allowed! (Levels 5 and higher) J. Kautzer

  7. SUSCEPTIBILITYResponses Disallowed by Rev 002 of EN60601-1-2(Example For Medical Products) J. Kautzer

  8. IEC61000-4-2 • Test Name: Electro Static Discharge (ESD) Immunity • Energy/Stress: Electrostatic Voltage • Simulates Real World Effect - ESD from human contact. Low humidity, low conductivity carpets, upholstery & garments are contributors • Equipment Used: Electrostatic Discharge Gun J. Kautzer

  9. IEC61000-4-2 • Coupling: Air Discharge, Direct Contact & Coupling Plane Discharge • Permutations: • Discharge points: Likely points of human contact with product including keyboards, monitors, operator controls, cabinet exteriors, removable media drives • Air or Spark Gap Discharge: 2000 volt increments to 8 kV • Direct Contact/Coupling Plane Discharge: 2000 volt increments to 6 kV • Positive and Negative Polarities for each discharge point • 10 hits per each discharge point J. Kautzer

  10. IEC61000-4-2 • Coupling Plane Discharge used for keyboard and mouse test J. Kautzer

  11. IEC61000-4-3 • Test Name: Radiated E-Field Immunity • Energy/Stress: Radiated Electromagnetic Voltage • Simulates Real World Effect – Radiated Frequency signals from Cell Phones, Radios, Cell & TV towers, CB’s , PC’s & other various electronic devices • Equipment Used: • RF Power Amplifier • Signal Generator Capable of Modulation • Transmitting Antenna and Isotropic Probe • RF Power meter • RF Directional Coupler & RF Reverb Chambers J. Kautzer

  12. IEC61000-4-3 (Rev 002) • Permutations: • Operational Modes including Imaging Modes • 3V/M RF Electric Field • RF Carrier is varied in 1% steps from 80Mhz to 2.5Ghz • Amplitude Modulation using 80% modulation factor @ 1kHz, Dwell Time (product response time) • As many as 56 Tuner (Horz and Vert Reflector) steps which covers 80% of the room height and width (80-300 Mhz) J. Kautzer

  13. IEC61000-4-3 (Rev 002) • Test Time: ~35 hours per operational mode using 6 second dwell time between steps. 6 seconds/step plus 6 second dwell time per step. (~10,500 total steps/mode!) • Initial testing may require longer dwell times to gauge product response • Only test the modes that are absolutely necessary! • Reverb chamber with “mode-stirs” must be utilized. Expensive! Need to plan test time and mode strategy well in advance! J. Kautzer

  14. IEC61000-4-4 • Test Name: Electrical Fast Transient & Burst (EFT) • Energy/Stress: Voltage Transients up to 2000 Volts • 50 nS Pulse with 5ns rise times - ~400V/nS • Simulates Real World Effect – Created on public power lines by electrical arcs across switch contacts during opening of inductive loads such as relays, motors and other commutations • Equipment Used: Coupler, Transient Generator & Scope • Coupling: Capacitive (I/O Cables) & Direct Injection (Main Power Input Cables). Capacitive coupling is a 1 meter long cable clamp of parallel plates. Energy goes right through the cable jackets! J. Kautzer

  15. IEC61000-4-4 • Permutations: • 500 Volt Increments • 2 Minutes/step • Positive and Negative Pulse Polarities for each Increment • AC Mains receive up to 15 injection points • I/O Cables > 3M length require both ends be tested up to 1 Kv • Main Power Cables are tested at up to 2 Kv regardless of length • Cautions: Must be done in shielded room as the test may create a large amount of RF energy J. Kautzer

  16. IEC61000-4-4 • Electrical Fast Transient Generator with Coupling Circuits J. Kautzer

  17. IEC61000-4-5 • Test Name: Power Input Surge Immunity • Energy/Stress: Voltage Surge Pulse • 50 uS open-circuit voltage pulse with 1.2 uS rise time • 20 uS short-circuit current pulse with 8 uS rise time • Simulates Real World Effect – Voltage surges caused by lightning discharges and switching disturbances in power stations • Equipment Used: Coupler, Surge Generator & Scope • Coupling: Direct Injection into System Mains Power) J. Kautzer

  18. IEC61000-4-5 • Permutations: • Differential Coupling (Phase-Phase) to 1 kV • Common Coupling (Phase-Ground) to 2 kV • 500V, 1 kV, 2 kV levels • Positive and Negative pulse polarities • Pulses at 90o increments of 360o AC input cycle. Many mfgs typically test at 45o • 5 pulses per phase angle increment • Minimum surge rate is 1/min J. Kautzer

  19. IEC61000-4-6 • Test Name: RF Conducted Immunity • Energy/Stress: Induced RF Voltage • Simulates Real World Effect – Lower frequency RF energy inductively coupled into system cabling • Equipment Used: Injection Probe, Coupler, Signal Generator, RF Amplifier, Current probe, Spectrum Analyzer & Calibrated fixture (LISN can be used in place of Injection Probe) J. Kautzer

  20. IEC61000-4-6 • Coupling: Inductively coupled into main power cables and all external I/O cables greater than 1 meter in length • Permutations: • Sweep Carrier frequency 150 kHz - 80 MHz in 1% steps • Amplitude Modulation 80% @ 1 kHz, 3 Vrms • AC mains and I/O cables that are routed together (Within same cable tray) J. Kautzer

  21. IEC61000-4-8 • Test Name: PF Magnetic Field Immunity • Energy/Stress: Power Frequency Alternating Magnetic Fields • Simulates Real World Effect – Magnetic fields generated from power distribution lines, switchgear, and other high-current circuits • Equipment Used: Magnetic field coil and power frequency variable transformer with stable constant current source (See Related standard IEC61000-2-7, Low Frequency Magnetic Field Environments) J. Kautzer

  22. IEC61000-4-8 • Coupling: Radiated, No Attachments • Permutations: • Excite three product axis • Horizontal Left-Right (X) • Horizontal Front-Back (Y) • Vertical (Z) • 3 Amps/Meter field (37 mG) using 50 or 60 Hz source • Cautions: Very difficult to get equipment immersed in the field (Bulky Coil) • Cautions: Example shown - Coil Frame is 10ft height X 11ft width, and is very difficult to position. Equipment setup needs to accommodate insertion of bucky coil frame on wheels J. Kautzer

  23. IEC 61000-4-11 • Name: Voltage Dip, Short Dropout & Variation Immunity • Energy/Stress: AC Voltage degradations (Power Brownout) and Voltage Dropouts • Simulates Real World Effect – Varying loads on AC power lines cause changes in the line voltage. • Equipment Used: Mains power disconnect switch and amplifier for products with line current <=16Amps/phase J. Kautzer

  24. IEC 61000-4-11 • Permutations: Drop out each phase of AC mains power individually • 5 second dropout regardless of current load • 4 test conditions with “rated line current” of I-phase <= 16 Amps • 100% dropout for 0.5 cycle • 40% Vnom for 5 cycles • 70% Vnom for 25 cycles • 100% dropout for 5 seconds J. Kautzer

  25. Standards Summary US/FCC:47 CFR 15 - Radio Frequency Devices 47 CFR 18 - Industrial Scientific and Medical Equipment IEC:60601-1-2 Electromagnetic compatibility - Requirements and tests 61000-3-2 EMC Part 3: Limits - Section 2: Limitation of harmonics in low-voltage supplies <16A 61000-3-3 EMC Part 3: Limits - Section 3: Limitation of voltage fluctuations and flicker in low-voltage supplies <16A 61000-3-5 EMC Part 3: Limits - Section 5: Limitation of voltage fluctuations and flicker in low-voltage supplies >16A 61000-4-1 EMC Part 4: Test/measurement techniques - Section 1: Overview of immunity tests 61000-4-2 EMC Part 4: Test/measurement techniques - Section 2: ESD immunity tests 61000-4-3 EMC Part 4: Test/measurement techniques - Section 3: Radiated radiofrequency immunity tests 61000-4-4 EMC Part 4: Test/measurement techniques - Section 4: Electrical fast transient/burst immunity tests 61000-4-5 EMC Part 4: Test/measurement techniques - Section 5: Surge immunity tests 61000-4-6 EMC Part 4: Test/measurement techniques - Section 6: Conducted radiofrequency immunity tests 61000-4-7 EMC Part 4: Test/measurement techniques - Section 7: General guide on harmonics measurement and instrum. 61000-4-8 EMC Part 4: Test/measurement techniques - Section 8: Power frequency magnetic field immunity tests 61000-4-9 EMC Part 4: Test/ measurement techniques - Section 9: Pulsed magnetic field immunity tests 61000-4-10 EMC Part 4: Test/measurement techniques - Section 10: Damped oscillatory magnetic field immunity tests 61000-4-11 EMC Part 4: Test/measurement techniques - Section 11: Voltage dips, short interruptions and variations CISPR:11 Limits and methods of measurement for Industrial, Scientific and Medical Equipment 16 Specifications for Radio Interference Measuring Apparatus and Measurement Methods 22 Limits and Methods of Measurements of Radio Interference of Information Technology Equipment J. Kautzer

  26. Standards Limits and Guidelines Summary J. Kautzer

  27. Standards Limits and Guidelines Summary J. Kautzer

  28. Test Plan Basics: Tests X Operating Modes = Test Time • Define System/Subsystem to be Tested • Catalog/BOM/Revision incl Accessories • List of Devices using external Cables • List of External cable interconnects (MIS) • List of Clocks within all Devices under test • Operating modes of interest • Table of Tests versus Modes (= Time!) • Define all applicable EMC tests • Table of operating modes per EMC test • Define Type of Test • Certification, Engineering, Audit • Define System/Subsystem Layout • Layouts (footprints) for OATS, Reverb Chamber, Screen Room J. Kautzer

  29. Basic Counter Measures • Circuit Designs: • If possible minimize the number of asynchronous clocks • Minimize the edge rate transition of digital signals, terminations • Minimize signal loop areas/impedances, use ground planes or parallel runs for signal returns • Cabling: • Ext signal cables fully shielded using 360o terminations, grounded • Grounded-Shielded connectors on signal cable bulkheads • Ferrites used on cables near high level, high frequency emissions • Enclosures: • Electronics in shielded enclosures with minimal slot dimensions • No floating metal, grounded, shield with minimal leakage current • Main Power Inputs: • Employ Line filter, Isolation Transformer or Surge Supression Devices • Keep unfiltered input wires away from filtered distribution wires J. Kautzer

  30. Cable Shielding Termination Autopsy Examples 2 sided non-conductive tape J. Kautzer

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