High-quality paints in a new light - Long-life LED tubular light fittings for efficient general lighting

LED tubular light fittings represent an outstandingly efficient alternative to conventional linear luminaires with transparent lens covers. The slim, lightweight devices that the paint manufacturer acquired from lighting manufacturer R. STAHL stand out for more than just their lighting technology parameters. They are also maintenance-free and extremely durable, lasting over 100,000 operating hours. These systems are vibration resistant, very impact resistant with IK10 protection, and available with a degree of protection up to IP68; they are not only suitable for use in particularly demanding industrial environments or restricted areas. They are equally suitable as a modern, cost-effective solution for standard-compliant general lighting in entire factory halls and production areas. Significant cost savings can be achieved in terms of both procurement and operating costs when installing LED tubular light fittings. For instance, 30 devices from the 6036 series, measuring just 140 cm in length, provide illuminance of around 500 lx, which would typically require 35 linear luminaires, each with two 36-watt fluorescent tubes. On one hand, this reduces the number of light fittings required. On the other hand, it also reduces energy usage, since the power consumption of the tubular light fittings is around half that of conventional lighting solutions.

Retrofitting LED light fittings

This is what motivated Karl Wörwag Lack- und Farbenfabrik GmbH & Co. KG, a leading manufacturer of paints for vehicle construction, household devices and the furniture industry, to retrofit their general lighting system using LED tubular light fittings from R. STAHL. The traditional business, which is based in Stuttgart-Zuffenhausen (Germany) and operates production facilities in all key global markets, is internationally active, specialising in the manufacture of high-quality liquid and powdered paints and lacquer foils. The systems and production processes used by the paint manufacturer, which is certified according to DIN EN ISO 14001 and EMAS II validated, stand out thanks to their high efficiency and environmental standards. In the wet paint segment, Wörwag covers the entire spectrum of organic and water-dissolved paints and paint systems – from primers to base coats, clear coats, topcoats, soft coats and decorative varnishes through to special products such as SMC coatings and UV paints. Innovative product ranges for filler-free painting that are applied in a wet-on-wet process without long drying times mean that painting times and emissions are reduced and significantly less energy is consumed. The powdered paints from Wörwag also protect agricultural and construction machinery against corrosion caused by wind and weather. They are additionally used as effect coats and topcoats in building technology and on bicycles, household devices and furniture. In automotive construction, both internal and external parts are coated with functional or decorative paints. Furthermore, the company manufactures several hundred thousand square metres of lacquer foil each year; these foils are used to enhance the look of plastic windows or to coat plastic attachments for vehicles. The use of lacquer foils saves around 70% more energy in comparison with other painting processes. What’s more, foil coatings, which are applied without the use of oversprays or other waste products, are extremely environmentally friendly and particularly efficient, with an ideal-typical efficiency rating of 100%.

Many criteria for high-quality lighting technology

The high quality requirements in paint production mean that optimum, even lighting is needed in all production areas, in accordance with DIN EN 12464-1 (Lighting of work places – Part 1: Indoor work places) and workplace regulations. Due to the lighting physics that differ from conventional fluorescent lamps, gas discharge lamps and halogen lamps when retrofitting modern LED technology, additional characteristic values must be taken into consideration alongside illuminance (lx), luminous flux (lm) and luminous efficacy (lm/W). For accurate colour perception, the colour rendering index must also be taken into consideration when selecting light fittings, in order to meet various lighting requirements and enable visual tasks to be performed. With good colour rendering index of at least Ra 80, the models in the 6036 series consistently meet the indoor work place requirements of DIN EN 12464-1. Since the colour temperature also plays a key role in workers’ attentiveness and wellbeing in the workplace, R. STAHL offers its LED tubular light fittings with three different colour temperatures. As well as the standard version with neutral white light (5000 K), a cold white version (6500 K) and a warmer version (4000 K) are available.

Ex-protected and silicone-free

What’s more, specific requirements are placed on the reliability and material characteristics of the light fittings. Explosive atmospheres may form during the manufacture of solvent-based paints; as a result, the luminaires must not pose any risk of ignition. As well as being explosion-protected and certified as per ATEX and IECEx, the device design must be free from any substances that could impair the adhesive properties of the paints. Molecular contaminants such as silicone, separating agents, lubricants, oils or other foreign substances can have a negative effect on the even adhesion of the surfaces to be painted. Measures must therefore be taken from the start to ensure that substances of this kind that are produced by equipment do not enter the production process and cannot contaminate the end product. Consequently, only explosion-protected devices with silicone-free seals were considered for use as general lighting in the paint manufacturer’s factory halls.

Professional lighting design

As a technological leader in explosion-protected LED lighting, R. STAHL’s tubular light fittings represent the development of one of the first industry-tested product ranges with silicone-free versions for hazardous areas. These systems, which are globally approved for use in explosion protection Zones 1/21 and 2/22, can be installed quickly and simply using pipe clamps. Thanks to their low, in-rush current, a large number of light fittings can be connected per circuit breaker. Before the light fittings were installed at the user’s premises, a detailed lighting design process took place, including a feasibility study that took into consideration the installation costs, energy efficiency and predicted maintenance costs. Based on their in-house ezyLum planning software, the lighting experts from R. STAHL tailored every aspect of the lighting technology to meet the spatial conditions and to suit the visual tasks to be performed. This program enables photorealistic visualisation of lighting solutions, thus allowing the experts to precisely replicate the spatial geometry, including relevant areas and standard objects. In this way, the number, position and alignment of the luminaires was determined down to the details, taking the required luminous flux and light distribution, beam angle and glare factor into account, in order to guarantee uniform, norm-conform nominal illuminance for every operating area.

In short

With comprehensive lighting technology expertise and a wide product range from their in-house lighting production facility, the explosion protection expert R. STAHL supports users when planning and modernising their lighting systems – from emergency, signal and safety lighting to general lighting. As a leading provider of industrially suitable LED light fittings, the company develops efficient lighting concepts for Ex and non-Ex areas in industrial and commercial systems for indoors and outdoors. When it came to the step-by-step process of retrofitting Wörwag’s factory halls and production facilities, R. STAHL once again implemented extremely efficient, cost-effective, outstanding lighting technology solutions thanks to its LED tubular light fittings. All expectations regarding the modernisation of the general lighting at the Stuttgart factory have been entirely met.