Photo: EMC Bayswater – Indoor Open Area Test Site (iOATS) chamber – Radiated emissions & Radiated Disturbances
Why is an indoor Open Area Test Site (iOATS) facility better than a shielded enclosure and an OATS test site
About the EMC Bayswater Indoor Open Area Test Site iOATS
Our indoor Open Area Test Site or commonly known as the iOATS was specifically designed and installed at our facility to cater for the demand of indoor testing of radiated emissions. Our Radiated Emissions test site provides a compliant valid testing environment which includes the test site been fully compliant with ANSI 63.4: 2009 and C63.4: 2014 required for FCC and IC testing.
Radiated emissions testing efficiency
Testing in a compliant iOATS facility has many advantages over performing emissions in a two-stage process. Which normally involves performing pre-scans in a non-compliant chamber or screened room and then performing the final measurements out on an outside test site. These advantages include a real representation of the emissions over the frequency range due to the low reflection of RF on the chamber walls. Screened rooms or chambers without adequate RF absorbing material such as ferrite tiles and RAM (RF Absorber Material) or physically unsuitable due to the dimensions of the chamber can create misleading results. These misleading results can be caused by constructive and destructive nodes at varying frequencies depending upon the reflections and size of the chamber and the relative position of the antenna, EUT and the conductive surfaces such as the chamber walls etc. This effect is typically worst at the lower end of the frequency range 30MHz to 300MHz.
Ambient emission free environment for Radiated Emissions
With no ambient emissions from outside influences such as TV, FM radio, transmitters etc whilst maintaining an equivalent open area test site characteristics. Measurements over the frequency range can be accomplished in less time. Although the hourly rate to use our iOATS facility is slightly more than using a non-compliant iOATS test site in most instances the total cost to perform the testing is cheaper as less time is required.
Radiated emissions single setup – Cheaper Radiated Emissions testing
Another advantage of using an iOATS test site where all the measurements can be performed in a single process is only having to set the Equipment Under Test (EUT) and the associated support equipment up once. This is also a significant time saving and obviously another significant cost saving. Not to mention the time delay caused by moving sites or having to drive, commute or send the product to a different location or possibly a different laboratory maybe interstate.
Calibration of the Radiated Emissions test site
Calibration of an OATS site is usually performed at a single position whilst the calibration of an iOATS site several positions are required that defines the boundaries of the Normalised Site Attenuation (NSA) volume. This NSA volume defines the maximum dimensions that a product can be measured whilst ensuring the test site is still compliant. On an OATS site, the dimensions or volume of the product under test is not considered. Our iOATS is ANSI C63.4-2014 calibrated from 30MHz to 1GHz with a test volume diameter of 3m. Our iOATS is also calibrated for Site Voltage Standing-Wave Ratio (SVSWR) with the preferred dimensions over the entire required frequency range of 1GHz to 18GHz as per CISPR 16-1-4 (CISPR 16-1-4), Edition 3.1 (2010 + A1: 2012).
Climatic control for repeat-ability and comfort
One obvious advantage not mentioned so far is the actual climatic conditions during the testing process itself. Rain, snow, high humidity or extreme variations in the weather may affect the radiated emissions results. These variations can cause an increase or decrease in the measured values and may make compliance uncertain for borderline compliant products. Thus the overall compliance status if the testing was to be repeated could be in jeopardy. Radiated Emissions re-testing does occur when there is an issue, dispute concerning the compliance or market surveillance and can occur at any stage over the life cycle of the product.
We recommend using a fully compliant suitable chamber for your product testing. If we cannot perform the testing in accordance with the standard you require we will upfront and clearly inform you of this. EMC Bayswater has a commitment to performing testing efficiently and correctly whilst providing great customer service.
EMC Bayswater indoor Open Area Test Site (iOATS) facility specifications
Our iOATS facility incorporates some very impressive features and has been characterised by extremely good results, here are some of the features:
- Complies with CISPR 11, CISPR 12 (ALSE 3m testing), CISPR 13, CISPR 14-1, CISPR 15, CISPR 16, CISPR 22
- NATA accredited to CISPR 11, CISPR 12, CISPR 13, CISPR 14.1, CISPR 15, CISPR 22, CISPR 32 (3m measurements)
- Calibrated NSA 30MHz to 1GHz test volume of 3m
- Accommodates most small to medium-sized products (As per CISPR 11, small equipment, either positioned on a tabletop or standing on the floor which, including its cables fits in a cylindrical test volume of 1,2 m in diameter and 1,5 m above the ground plane).
- Complies with CISPR 25 for automotive component EMC testing
- Compliant with FCC Part 15 and ANSI C63.5 (meets the NSA requirements for a semi-anechoic chamber) registered with the FCC and Industry Canada
- Compliant with ANSI C63.4-2009 and the latest ANSI C34.4-2014 (meets the NSA and antenna requirements for a semi-anechoic chamber up to 18GHz)
- Conveniently located in Bayswater in Melbourne’s outer eastern suburbs (close to East Link tollway)
- 100% ambient free, extremely efficient testing and fast turnaround time
- Large double entry doors (3.5m X 3.5m)
- Length 10.7m, width 7.2m and height 6.0m
- Can accommodate large EUTs such as Industrial Machines (conditional testing)
- Filtered mains power (single and three phase 50Hz 32A per phase, 115VAC 60Hz)
- Accommodation of ancillary equipment in external shielded annex chamber
- LAN and WLAN access for exercising Equipment Under Test (EUT)
- Many ports available for external ancillary equipment via chamber penetration connectors, wave-guides and filters
- Automated fibre-optically controlled mast and turntable
- Measurements were taken with modern 40GHz (Rohde & Schwarz) CISPR compliant EMI Receiver
- Independently verified to CISPR and FCC requirements
- Can accommodate 3m and 5m EMC measurements
- Vehicle testing capability – Full vehicle exhaust extraction system