SERVICES !!

17025 ACCREDITED TESTING/MEASUREMENT OF SHIELDING EFFECTIVENESS !!

BNN Offers calibration and measurements of shielding rooms, semi anechoic chambers, fully anechoic rooms and other test sites used for EMC measurements between 9 KHz to 40 GHz.

The onsite testing/measurement of Shielding Effectiveness is carried out as per following scope:-

  • IEEE 299: 2006.
  • Enclosures and boxes having all dimensions between 0.75m to 2m as per IEEE 299.1: 2013.
  • Appendix A of MIL Std. 188-125.2: 3 Mar 1999.

 Shielding Effectiveness

BNN has carried out Shielding Effectivenesss measurements for following two SAR Laboratories in Delhi NCR:-


Presentation on Shileding Effectiveness Measurements

Flyer on Shileding Effectiveness

SITE VSWR (sVSWR) Measurements !!

EMI test sites for radiated emission measurements in the 1 GHz to 18 GHz Require site validation by measurement of site voltage standing wave ratio (SVSWR), which is the ratio of the maximum received signal to the minimum received signal caused by interference between direct (intended) and reflected signals. There are two different approaches for showing compliance with the acceptance criterion:

  • The SVSWR method in line with CISPR 16-1-4. This requires special antennae described in the standard
  • The new time domain SVSWR (TD SVSWR) method in line with the ANSI C63.25 (Draft stage)
BNN is equipped to undertake site VSWR measurements by both the methods using traceable equipment and Antennae. 		sVSWR

Normalised Site Attenuation (NSA) Measurements !!

The NSA measurements (30MHz to 1GHz) are carried out to determine suitability of a Semi Anechoic Chamber or an Open Area Test Site for undertaking the Radiated Emissions test as per CISPR 16-1-4.

BNN has Antennae/equipment with traceable calibration and trained engineers to undertake NSA measurements for OATs and Semi Anechoic Chambers. 		NSA

Field Uniformity (FU) Measurements !!

The Field Uniformity measurements as per IEC 61000-4-3 (80MHz-18GHz) are used to validate test sites for radiated immunity measurements and are also required to generate necessary calibration files used during subsequent testing.

BNN has a 17025 calibrated EMF probe upto 18GHz to undertake these measurements..

FU

Absorber Line Shielded Enclosure (ALSE) Performance validation Measurements !!

The Modelled Long wire (Long Wire) measurement confirms the conductivity and grounding of a mettalic test table used in automotive EMC measurements within an ALSE. The enclosure is lined with ferrite and other radio freqeuency absorbing methods.

Testing is undertaken using a special Long wire antenna along with Bi-conical and Log Periodic antennae

FU

Absorber Reflectivity Testing !!

Performance of EMC/EMI Chambers largely depends on performance of absorber which may deteorate over time. This can be undertaken as per following Standards/Methods both onsite & in the Laboratory.

(a) Reflectivity in-Lab ( IEEE 1128, NRL Arch Method).

(b) Reflectivity in-Lab/Onsite ( RCS Method, IEEE AMTA 2016.

 FU

Normalised Site Attenuation Loss(NSIL) !!

Semi Anechoic Chambers & OATS are now being evaluated from 9KHz-30MHz in order to use them for magnetic field emission testing as per CISPR 16-1-4:2023 for these evaluations, magnetic field Antenna ( Loop ) in all three orthagonal arrangements ( HX, HY & HZ ) are used. Similar to classical VSA validation, the volumetric test method is applied.

BNN can undertake Certification of the existing chambers ( 3m, 5m & 10m ) as per the new Standard.

 FU