State-owned power utility Eskom’s Swan Edison Illumination Laboratory is in the process of obtaining accreditation from the South African National Accreditation System (Sanas) to enter the commercial and residential lighting market.
Eskom opened the laboratory in 2014 at its Research and Innovation Centre, in Rosherville, east of Johannesburg, to test and verify the performance of lamps and luminaires.
The laboratory is one of only a few in South Africa that can test all the colour parameters of lamps and luminaires, and one of only a few that is equipped with all the instruments required for the testing, and research and development (R&D) of lighting.
One such instrument is the Electronic Ballast tester, specifically designed to test the electronic ballasts of linear fluorescent and compact fluorescent lamps, with input and output and electrical performance properties of the ballast being tested simultaneously.
The tester can also be preset to upper and lower limits based on standards and specifications to be met for the automatic judgment of the electrical performance properties of the ballast. It is also suitable for performing line site tests, quality inspection and R&D for fluorescent lighting.
Another instrument is the Integrating sphere, which is used for spectra, colour and photometric measurement on light-emitting diodes (LEDs) and other lighting sources or lamps.
Eskom Research and Innovation Centre senior adviser André Blignaut explains that during testing, the testers only focus on measuring the spectrum and colour quality of light visible to humans, for example, red and blue light, which is used as an indication in the classification of lamps between warm white to cool white light. These variations are used in the description labels on packaging in which the lights are sold.
The 4 t Goniophotometer machine, an instrument also owned by the laboratory, measures and calculates light intensity and photometry. This is a photometer for measurement of the angular dependence of optical quantities. It is applicable to acquire the luminous intensity distribution, luminous flux, spatial colour distribution, and luminance distribution of lamps and luminaires.
The machine’s design includes a variety of measuring principles that can be applied to all kinds of lamps, as well as LED, indoor, outdoor, street, flood and traffic luminaires.
“The Goniophotometer is recognised for its high stability, high measurement speed, highest luminous flux accuracy, flexible configuration, wide dynamic range of measuring light intensity, ultralow stray light and high- angle accuracy,” Blignaut notes.
Once the machine is switched on, the mirror attached performs a self-calibration to centre itself on a C axis. It then starts rotating 360° constantly around the light fitting that is being tested.
Blignaut mentions that the light is then reflected onto an additional mirror at the opposite end of the room, 10 m away. The light then reflects back into a tube adjacent to the mirror. This process is used to determine the intensity of the light fitting that is being tested.
Meanwhile, the laboratory verifies and ensures that Eskom installs and procures good-quality illumination products and that they will provide the best illumination where installed and, more importantly, that the installations meet Occupational Health and Safety Act requirements.
Blignaut notes that South Africa has limited accredited facilities that test safety and performance standards of lighting products. The laboratory is working hand in hand with the South African Bureau of Standards and is a member of the Illumination Engineering Society of South Africa.
He asserts that Eskom recognises the contribution lighting can make to achieve the national energy efficiency objectives, with lighting and sensors offering countless opportunities – not only for residential customers but also the commercial, industrial and agriculture sectors.
Blignaut hopes that the laboratory will receive accreditation by the end of this year.