⚡ EMC testing — electromagnetic emission
In short
Testing of conducted and radiated electromagnetic emission according to PN-EN 55032. The test is performed according to PN-EN 55032:2015/A11:2020 (CISPR 32); Conducted emission range: 150 kHz – 30 MHz. The procedure comprises 10 steps (about 10 h–18 h 30 min in total); it is used for: CE certification of multimedia equipment (computers, monitors, printers, routers), EMC testing of telecommunications and IoT devices, Qualification of switch-mode power supplies and DC-DC converters.
At a glance
- Standard: PN-EN 55032:2015/A11:2020 (CISPR 32)
- Category: Electronics and EMC
- Procedure steps: 10
- Total time of stages: 10 h–18 h 30 min
- Conducted emission range: 150 kHz – 30 MHz
- Radiated emission range: 30 MHz – 6 GHz (up to 18 GHz for some devices)
- Quasi-peak detector (QP): Main detector according to CISPR 16-1-1, charge time constant 1 ms, discharge 160 ms
Overview
Electromagnetic emission testing (EMI — Electromagnetic Interference) is a key element of the electronic device certification process in the European Union. The PN-EN 55032 standard (implementation of international CISPR 32) defines permissible emission limits for electromagnetic interference from multimedia equipment — computers, monitors, printers, routers, televisions, audio/video systems, and telecommunications devices.
The standard covers two main types of emission: conducted emission in the range 150 kHz – 30 MHz, measured on power lines using an artificial mains network LISN, and radiated emission in the range 30 MHz – 6 GHz, measured with an antenna in an anechoic chamber or on an open area test site (OATS). The standard defines two device classes: class A (industrial environment, less stringent limits) and class B (residential environment, stricter limits).
EMC emission testing is mandatory for obtaining CE marking in accordance with EMC Directive 2014/30/EU. A manufacturer or importer cannot place an electronic device on the European market without demonstrating compliance with PN-EN 55032 (or the standard appropriate for the product category). Tests are performed in accredited EMC laboratories equipped with shielded and anechoic chambers.
The cost of complete EMC testing (emission + immunity) in an accredited Polish laboratory ranges from several to several tens of thousands of PLN, depending on device complexity and test scope. Test time is typically 2–5 working days.
Method principle
Conducted emission: The equipment under test (EUT) is connected to the mains supply via an artificial mains network (LISN — Line Impedance Stabilization Network), which provides defined 50 Ω impedance and isolates mains noise from device noise. The interference signal from LISN output is measured with an EMI receiver (quasi-peak and average) or spectrum analyzer in the 150 kHz – 30 MHz range. Radiated emission: EUT is placed in an anechoic chamber (semi-anechoic chamber) on a turntable at a distance of 3 m or 10 m from the measuring antenna. The antenna (bilog or horn) scans the electromagnetic field in the 30 MHz – 6 GHz range, rotating EUT 360° and changing antenna height (1–4 m) searching for maximum emission. Measured levels are compared with class A or B limits.
Applications
- CE certification of multimedia equipment (computers, monitors, printers, routers)
- EMC testing of telecommunications and IoT devices
- Qualification of switch-mode power supplies and DC-DC converters
- Testing of audio/video equipment and home entertainment systems
- Verification of EMC prototypes in product development phase (pre-compliance)
- Testing of industrial equipment (controllers, PLC, drives)
- Compliance assessment of electronic modules (Bluetooth, Wi-Fi, LTE)
Key parameters
| Parameter | Value |
|---|---|
| Conducted emission range | 150 kHz – 30 MHz |
| Radiated emission range | 30 MHz – 6 GHz (up to 18 GHz for some devices) |
| Quasi-peak detector (QP) | Main detector according to CISPR 16-1-1, charge time constant 1 ms, discharge 160 ms |
| Average detector (AVG) | Averaging detector, limit 10–13 dB below QP |
| Measurement distance (radiated emission) | 3 m or 10 m (10 m preferred, results converted) |
| Class B — example limit 30–230 MHz | 30 dBµV/m (QP) @ 10 m |
Standard
- Standard number
- PN-EN 55032:2015/A11:2020 (CISPR 32)
- Title (PL)
- Kompatybilność elektromagnetyczna urządzeń multimedialnych — Wymagania emisji
- Title (EN)
- Electromagnetic compatibility of multimedia equipment — Emission requirements
Step-by-step procedure
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Test plan preparation
Determine device class (A/B), ports to test (AC/DC power, signal, telecommunications), EUT operating modes. Prepare test configuration.
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EUT configuration
Set device on measuring table (height 80 cm for floor-standing, 80 cm + table for tabletop). Connect to LISN and signal cables. Insert all cables in typical usage configuration.
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Conducted emission — preliminary measurement
Measure emission on power ports using LISN + EMI receiver in 150 kHz–30 MHz range. Perform scan with peak detector.
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Conducted emission — final measurement
Measure critical frequencies (from step 3) with quasi-peak and average detectors. Compare with class A/B limits. Repeat for all power lines (L, N, PE).
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Radiated emission — chamber setup
Place EUT on turntable. Set antenna on mast at distance of 3 m or 10 m. Configure horizontal and vertical polarization.
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Radiated emission — prescan
Perform quick peak scan in 30 MHz–1 GHz range (and up to 6 GHz), rotating table every 15° and scanning antenna height 1–4 m. Identify critical frequencies.
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Radiated emission — final measurement
At identified critical frequencies, measure QP level, maximizing signal (table rotation, antenna height, polarization). Compare with limits.
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Telecommunication port emission
If device has network ports (Ethernet, USB, HDMI) — measure conducted emission on these ports according to standard requirements (voltage or current).
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Result analysis and margin
Compare measured levels with limits. Calculate margin = limit − measurement. Margin >6 dB = safe, 3–6 dB = acceptable, <3 dB = risky.
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Test report
Prepare report containing: EUT identification, test configuration, measuring equipment, environmental conditions, results (graphs + table), compliance assessment, photos.
Required equipment and apparatus
| Equipment | Example | Indicative price |
|---|---|---|
| Semi-anechoic chamber | ETS-Lindgren, Rohde & Schwarz, TDK, 3 m or 10 m | 500 000–5 000 000 PLN |
| EMI receiver / spectrum analyzer | Rohde & Schwarz ESR/ESW, Keysight N9038A MXE, 9 kHz–26.5 GHz | 150 000–600 000 PLN |
| Artificial mains network LISN (50 µH / 50 Ω) | Rohde & Schwarz ENV216, Schwarzbeck NNLK 8129, Rohde & Schwarz ESH3-Z5 | 15 000–50 000 PLN |
| Bilogarithmic antenna (BiLog) | Schwarzbeck VULB 9163, ETS-Lindgren 3142E, 30 MHz–6 GHz | 20 000–60 000 PLN |
| Turntable + antenna mast | ETS-Lindgren 2090/2060, remotely controlled | 30 000–80 000 PLN |
| Measurement automation software | Rohde & Schwarz ELEKTRA, Keysight EMC32, ETS-Lindgren TILE! | 30 000–100 000 PLN |
Reagents, media and consumables
| Reagent | CAS | Details |
|---|---|---|
| Low-loss coaxial cables | — | RF measurement cables 50 Ω with N-type connectors, precision, certified, length 3–10 m |
| RF attenuators and adapters | — | Attenuators 3/6/10/20 dB, adapters N-SMA-BNC, 50 Ω terminators |
| Antenna calibration standards | — | Antenna calibration certificates from accredited laboratory, valid 1–2 years |
Health and safety (OHS)
- Anechoic chamber — high RF voltages, do not enter during measurement
- Electromagnetic field — during immunity tests (not emission) strong fields may occur, apply exposure limits
- EUT under voltage — maintain electrical safety procedures (isolation, grounding)
- RF cables and connectors — protect from mechanical damage, control tightening torques
Frequently asked questions
Which standard describes this test?
The test is performed according to PN-EN 55032:2015/A11:2020 (CISPR 32) — “Electromagnetic compatibility of multimedia equipment — Emission requirements”.
How does this method work?
Conducted emission: The equipment under test (EUT) is connected to the mains supply via an artificial mains network (LISN — Line Impedance Stabilization Network), which provides defined 50 Ω impedance and isolates mains noise from device noise. The interference signal from LISN output is measured with an EMI receiver (quasi-peak and average) or spectrum analyzer in the 150 kHz – 30 MHz range.
What is the measuring range and accuracy?
Conducted emission range: 150 kHz – 30 MHz; Radiated emission range: 30 MHz – 6 GHz (up to 18 GHz for some devices); Quasi-peak detector (QP): Main detector according to CISPR 16-1-1, charge time constant 1 ms, discharge 160 ms; Average detector (AVG): Averaging detector, limit 10–13 dB below QP.
How long does the test take?
The times given for the individual stages add up to approximately 10 h–18 h 30 min. The procedure comprises 10 steps.
What equipment is required?
Semi-anechoic chamber, EMI receiver / spectrum analyzer, Artificial mains network LISN (50 µH / 50 Ω), Bilogarithmic antenna (BiLog), Turntable + antenna mast, Measurement automation software. Indicative cost of the core instrument (Semi-anechoic chamber): 500 000–5 000 000 PLN.
Where is this test used?
CE certification of multimedia equipment (computers, monitors, printers, routers); EMC testing of telecommunications and IoT devices; Qualification of switch-mode power supplies and DC-DC converters; Testing of audio/video equipment and home entertainment systems; Verification of EMC prototypes in product development phase (pre-compliance); Testing of industrial equipment (controllers, PLC, drives); Compliance assessment of electronic modules (Bluetooth, Wi-Fi, LTE).
What safety precautions apply?
Anechoic chamber — high RF voltages, do not enter during measurement; Electromagnetic field — during immunity tests (not emission) strong fields may occur, apply exposure limits; EUT under voltage — maintain electrical safety procedures (isolation, grounding); RF cables and connectors — protect from mechanical damage, control tightening torques.
Which laboratory can perform this test?
The test is performed by laboratories accredited to ISO/IEC 17025. On LabCoda you can find them by the standard number PN-EN 55032.