EMC & EMI


Electromagnetic interference & Electromagnetic compatibility lab

EMI/EMC

GARC has a full-fledged EMI/EMC facility which primarily focuses on pre-compliance and compliance tests for automobiles and its electronic sub-assemblies (ESA). This includes EMI/EMC testing for electric vehicles also. Apart from this, the lab also is capable to perform EMI/EMC tests on industrial, scientific, medical and other electrical/electronic equipments.

1) Vehicle tests:

The vehicle level tests include Radiated emission & radiated immunity tests which are done in an Absorber lined semi-anechoic enclosure (ALSE). GARC EMI/EMC lab includes two ALSEs of dimensions – 30mx20mx10m and 19.5mx12mx8m respectively. The ALSE chambers are equipped with 11m & 6m diameter turntables integrated with chassis dynamometers (4×4) respectively. 

The RF emission measurement systems (Radiated Emission) for vehicle level tests are capable of measurement from 30MHz to 18GHz for off-board tests and from 1.8MHz to 2GHz for on-board tests. The test can be performed as per AIS004 part-3, CISPR 12, CISPR 25, ECE R10 & OEM standards

The RF immunity measurement systems (Radiated Immunity/susceptibility) for vehicle level tests are capable of generating radiated immunity field in the frequency range of 100 kHz to 18GHz with severity levels up to 200V/m. The test can be performed as per AIS004 part-3, ISO11451-2, ECE R10 & OEM standards

The ALSE chambers in combination with its chassis dynamometer systems and test instrumentation enable the lab to perform EMI/EMC tests on wide range of automobiles which include 2 wheelers, 3 wheelers, passenger cars, light commercial vehicles & heavy commercial vehicles.

2) Electronic sub-assembly tests (Automotive):

The EMI/EMC tests for automotive ESAs at GARC EMI/EMC lab include test setups listed below,

a) Radiated emission & immunity:

The radiated emission & immunity tests are performed inside the ALSE chambers on a metal top table. Frequency range is from 150 KHz to 18GHz for emission test and from 20MHz to 18GHz for immunity test.

Apart from the ALSE method, setups like TEM cell, Stripline, Bulk current injection & Tri-plate are also available for immunity test. Tests can be performed as per AIS004 part-3, CISPR 12, CISPR 25, ECE R10, ISO 11452-2/3/5, SAE & OEM standards

b) Bulk current injection (BCI):

The BCI test is a harness excitation test method for determining the immunity of ESAs. GARC EMI/EMC lab includes test bench for performing the test from 1MHz to 400MHz using current probe (max current 300mA) and from 400MHz to 3GHz using Tubular wave coupler (TWC). Test can be performed as per ISO 11452-4 standard.

C) Conducted emission test:

The conducted emission test is performed inside a shielded room on a metal top table. Measurements through voltage method and current probe method are possible. The frequency ranges are 150 kHz to 108MHz and 150 kHz to 245MHz respectively. Test can be performed as per CISPR 25 standard.

d) Conducted transient immunity test:

The conducted transient immunity test involves subjecting ESA to electrical transient disturbances through supply lines/data lines and evaluating functional performance during and after the test. The pulse generator is capable of generating the typical ISO 7637 test pulses including 1, 2a, 2b, 3a, 3b, 4, 5a & 5b. The test bench can support conducted transient immunity test on 12V, 24V & 48V ESAs with a max current rating up to 100A (continuous). Signal line testing can be done through CCC, ICC & DCC methods. Test can be performed as per  ISO 7637-2/3 test standards.

e) Conducted transient emission test:

The conducted transient emission test is used to evaluate automotive electrical and electronic components for conducted emissions of transients along battery fed or switched supply lines of an ESA. Test can be performed on 12V, 24V & 48V ESAs with max current rating up to 100A. Test can be performed as per ISO 7637-2 test standard.

f) Electrostatic Discharge test (ESD):

The ESD test setup simulates an electrostatic discharge into a vehicle electrical system/ESA. GARC EMI/EMC lab has ESD simulators capable of air discharge & contact discharge modes up to 30kV. Test can be performed as per ISO 10605 standard.

g) Over voltage test:

Over voltage test simulates the condition where the alternator regulator fails so that the      output voltage of the alternator rises above normal values which affect the ESA. Test can be performed on 12V, 24V & 48V ESAs with max current rating of 100A as per ISO 16750-2 standard.

h) Super imposed alternating voltage test:

Super imposed alternating voltage simulates a residual AC on the DC supply. Test can be performed on 12V, 24V & 48V ESAs with max current rating of 100A as per ISO 16750-2 standard.

i) Slow decrease and increase of supply voltage test:

This test simulates a gradual discharge and recharge of the battery. Test can be performed on 12V, 24V & 48V ESAs with max current rating of 100A as per ISO 16750-2 standard.

j) Momentary drop of voltage test:

This test simulates the effect when a conventional fuse element melts in another circuit. Test can be performed on 12V, 24V & 48V ESAs with max current rating of 100A as per ISO 16750-2 standard.

k) Reset behavior at voltage drop test:

This test verifies the reset behavior of the DUT at different voltage drops. This test is applicable to ESAs with reset function [e.g. equipment containing microcontroller(s). Test can be performed on 12V, 24V & 48V ESAs with max current rating of 100A as per ISO 16750-2 standard.

l) Starting Profile test:

Starting profile test verifies the behavior of an ESA during and after cranking. Test can be performed on 12V, 24V & 48V ESAs with max current rating of 100A as per ISO 16750-2 standard.

m) Reverse voltage test:

The reversed voltage test checks the resistance of an ESA against the connection of a reversed battery in case of using an auxiliary starting device. Test can be performed on 12V, 24V & 48V ESAs with max current rating of 100A as per ISO 16750-2 standard.

3) Commercial equipment tests:

Apart from the automotive EMI/EMC tests listed above, the EMI/EMC lab at GARC include the test setups listed below for commercial equipments,

a) Harmonics & flicker emission test:

Harmonics & flicker test measures the harmonic current and flicker generated by the DUT. The test setup includes programmable AC source with impedance network with 75A max current rating, power analyzer as per IEC 61000-3-2, IEC 61000-3-3 & IEC 61000-3-11, IEC 61000-3-12 standards.

b) Electrical fast transient test (EFT):

The EFT test determines the immunity of DUT to repetitive electrical fast transients/burst. The test setup includes a EFT generator with single phase CDN with 16A and 3-phase CDN with 100A current rating. Test can be performed up to ±4kVwith 5 kHz and 100 kHz repetition frequency. The test setup also includes capacitive coupling clamp for signal line. Test can be performed as per IEC 61000-4-4 standard.

c) Combinational wave surge test:

This test is to determine the immunity of the DUT to unidirectional surges caused by switching and lightning transients. The test setup includes a surge generator with single phase CDN with 16A and 3-phase CDN with 100A current rating. Test can be performed up to ±6kV as per IEC 61000-4-5 standard.

d) Voltage dips, short interruptions & voltage variations:

This test is to determine the immunity of the DUT to voltage dips, short interruptions & voltage variations occurring in a low voltage power supply lines. The test setup includes a generator with inbuilt CDN up to 16A max current rating. Test can be performed as per IEC 61000-4-11 standard.

4) EMI/EMC simulation software:

GARC EMI/EMC lab is equipped with Altair FEKO v2020, an EMC simulation software which helps in design of radio and TV, wireless, cellular, communication, remote keyless entry, tire pressure monitoring, satellite positioning, radars, RFID, and other antennas. The software also helps in the placement of an antenna in a vehicle body to achieve maximum range/reception.

5) Upcoming facilities:

1) Component semi anechoic chambers:

Two new ALSE chambers of dimensions 8.5mX9.8mX7m and 8.6mx5.3mx6.1m exclusively for component level testing and On-board radiated emission & immunity test of 2/3 wheelers & 4-wheelers up to 4 tonnes.

2) Up gradation of existing ALSE chambers for testing of EV/EVSE:

The up gradation involves provisioning of charging test environment intended for testing Electric vehicles of categories 2W/3W/4W/HCV&EVSEs in the existing ALSE chamber.

AC emulation: min continuous 75A, 3Ph and 60kVA

DC emulation: min.720 kW, 1000 A DC, 1000 V DC

The up gradation will enable the testing of EV & EVSE as per ECE R 10.05 and AIS 138 (Part 1 & 2) standards.

3) Test setup for immunity to supply voltage harmonics:

Involves the setup of test bench for performing the immunity to supply voltage harmonics as per latest edition of IEC 61000-2-2, AIS 138 (Part 1), AIS 138 (Part 2)