Innovations in the EMC Laboratory

Electromagnetic compatibility (EMC) encompasses the influence and effects of
ectromagnetic fields that are emitted by the operation of electrical and electronic equipment.

Electromagnetic compatibility testing detects the ability of devices or systems to
function satisfactorily in an electromagnetic environment, but also the radiated intensity of electromagnetic interference that could affect the functionality of other devices. Since 1993, the EMC tests have been carried out by the EVPU in its accredited laboratory, which include in particular measurements of electromagnetic wave emissions, the detection of immunity to electromagnetic waves and tests of voltage changes. It carries out these tests in accordance with the relevant international standards for civil equipment (STN EN IEC 61 000 …. ), but also in accordance with the military standard represented by MIL STD -461 D, E and F. For military and aeronautical equipment, specified tests are carried out to protect these and other systems from interference, such as radio equipment. To effectively address these potential operational issues, testing is required to expose “vulnerabilities”. Equipment that must meet the requirements of MIL STD-461 is tested, e.g., by the RE102 – Measurement of Radiated Electric Field Emissions test, in the frequency range 10 kHz to 18 GHz. Although this test is similar to the measurement of the level of the electrical component carried out according to EN IEC 61 000 (non-military equipment), MIL STD-461 has its own specificities and different requirements defined also by the use of receiving antennas whose dimensions are precisely defined:

• Antenna 200 MHz – 1 GHz, “Double ridge horn”, apetura 69,0 cm x 94,5 cm;
• Antenna 1 GHz – 18 GHz, “Double ridge horn”, apetura 24,2 cm x 13,6 cm

At the end of 2022, new antennas were purchased for EVPÚ a. s. from the manufacturer A.H. Systems, Inc. California, USA with the designation SA-570 and SAS-571. Both antennas were calibrated by the manufacturer and calibration certificates were also included in the delivery.

Another significant innovation in the EMC laboratory in 2022 was the purchase of a new test receiver of the highest development series from Rohde & Schwarz, type ESW 26. This receiver meets the most stringent requirements in accordance with CISPR, EN, MIL STD-461, DO 160 and FCC standards.

Measurements and tests shall be carried out in a Semi-anechoic chamber with dimensions (L x W x H): 20.5 m x 12.4 m x 7.80 m or an anechoic chamber with dimensions (L x W x H): 7.30 m x 3.40 m x 3.60 m, in which the following parameters shall be achieved for each test:

• Emission tests: frequency range: 9 kHz – 26 GHz
• Line emission tests: Frequency range: 9 kHz – 30 MHz
• RF electromagnetic field immunity tests: Frequency range: 26 MHz – 18 GHz
• Electrostatic discharge immunity test: Air: up to 15 kV; Contact : up to 8 kV
• Test for immunity to interference induced by high-frequency fields, propagated by
  power lines: Frequency range: 150 kHz – 230 MHz
• Shock impulse immunity test: up to 4 kV
• Test for resistance to fast electrical transients/pulse groups: up to 4 kV

EVPÚ in an accredited EMC laboratory provides:

• measurement of the magnetic and electric component of the electromagnetic field;
• measurement of the level of disturbing clamp voltage;
• measurement of radiated power;
• measurement of the level of the electric component of the electromagnetic field;
• measurement of the level of the magnetic component of the electromagnetic field;
• measurement of low-frequency currents;
• measurement of voltage amplitude changes in the distribution network;

• detection of resistance to electrostatic discharge
• detection of immunity to interfering of a disturbing electromagnetic field;
• detection of resistance to electrical impulse bursts (burst test);
• testing for immunity to voltage surges;
• detection of resistance to induced RF currents;
• detection of resistance to magnetic fields (nf, pulsed, damped oscillating);
• detection of resistance to oscillatory waves, harmonic and interharmonic. voltage in the distribution network;

• test by short-term changes in supply voltage;
• test by supply voltage changes;
• low-frequency voltage test;
• overvoltage oscillating wave test;
• voltage frequency variation test;