Battery development enhances emergency lighting reliability

The EM ready2apply is a new and highly effective solution to the problem of reliable and compact emergency lighting, which unites Tridonic’s lighting expertise with some of the most rigorous testing processes to deliver a product that sets a bench mark for future emergency lighting solutions.

Chris Slattery, Global Product Manager for Emergency Lighting at Tridonic, explained: "Our aim was simple. Design a compact and easy to install product that would fit into an ever-diminishing ceiling void and through a minimal cut-out. It had to encompass sufficient power to exceed the necessary performance figures, exceed all lifetime and safety requirements, as well as give users the option on installation with interchangeable lenses.” The company wanted to progress from the traditional design of using a hinged inverter or a battery in a protective sock to deliver a product that was both more aesthetic and user friendly.

From concept to release it has taken four years and the combined design and engineering skills of Tridonic’s emergency lighting team based in Spennymoor, strengthened by other engineers around the globe, to complete the robust design and testing procedures. At the heart of the process were some of the most stringent safety and reliability criteria. The first challenge was to find a battery that would be small enough but also pack enough power for all possible applications. The current NiCd and NiMH technologies would not deliver the required performance relative to their size so the search for an alternative started in May 2013. After extensive research and testing far beyond the basic levels required, Tridonic settled on a LiFePO4 battery which exceeded all the safety, lifetime, and performance requirements they had set.

“Next we set about the challenge of combining an LED driver, battery charging circuit, DALI interface, and monitoring circuit inside a space of approximately 75x35x25mm,” continued Chris. “We then had to add two cut-outs on the PCB for the springs that keep the luminaire in the ceiling. This was finally made possible using some clever engineering and a flexi-rigid PCB which allows for the optimal use of available space.”

The development team then needed to work out the best means of connecting the battery. Their solution connects the two parts together, allows the product to flex over on installation, contains all the wiring required for the battery and protection circuit, provides a strong strain relief, and contains a simple two step method for battery connection and disconnection.

The EM ready2apply combines all the above with an interchangeable lens design to give the user a choice of how they want the product to perform without stocking separate units, the 'BlackBox' monitoring gives over 40 data points, the design for manufacture reduces operation steps to provide a cost and time efficient production, and ultrasonic welding is used to finally seal the housing shut (clips took up too much space).

The product is readily available through Tridonic’s proven network of approved distributors or over the counter at electrical wholesalers. The key elements of its specification are as follows:

• Maintained and non-maintained variants
• Basic, self-test, and DALI (PRO)
• Three interchangeable lenses with push-click-connection (anti-panic, escape route and spot)
• Impressive spacings with lens technology.
• Battery with an eight year design life and three year guarantee
• Five year electronics guarantee.