Central battery back-up system or self-contained emergency luminaires?

BLE Lighting and Power

What is the best option?

Central battery back-up system or self-contained emergency luminaires? Both have their own advantages. Depending on the project, the decision to use either is likely to be dependent on cost, layout and the size of the building(s). If an installation has long lasting low maintenance as a priority then a central battery may be the best option. If it is just a case of cost then you may want to choose self-contained.

Emergency lighting systems must be designed and installed to meet the requirements of British Standard 5266 Code of Practice. You can find out more about BS 5266 here.

 

Central battery systems

Central battery systems are normally used for the larger projects. A large multi-storey office block, for example, would require a central battery system  to keep the ongoing operational costs at a minimum.

They can be connected directly to suitably designed mains luminaires without modifications and they also operate at full light output under both ‘mains healthy’ and ‘mains failed’ conditions, making the whole system straight forward.

Maintained lights or signs are controlled under a central battery system by sub circuit monitors which activates if the mains power fails.

Another major advantage is that the battery life in a central system is maximised, usually lasting at least 10 years.

When replacement is eventually required, this is usually a quick and simple operation that avoids the disruption caused by having to access and dismantle numerous fittings to change batteries in public areas.

Central systems are simple to test, simple to maintain, provide completely unobtrusive emergency lighting and offer long-term cost advantages.

 

Self-contained luminaires

Self-contained emergency luminaires provide the simplest and quickest solution as they contain their own batteries and operate independently. They are less time-consuming to install, easy to extend or alter at a later date, and are usually the most cost-effective solution for small-to-medium sized projects.

The cost of installation can be relatively cheap because there is no need for any special, fire-rated cabling and they offer greater system integrity as each luminaire is independent of the others, so no special sub-circuit monitoring is required.

However, each product will require maintenance and regular testing, typically having a functional, short test each month and a full duration test each year. They have a battery life of only 3-5 years. Battery replacement takes approximately one hour per fitting and will require possible access equipment, this can represent a significant ongoing cost for the building operator.

Self-contained emergency luminaires can also be affected by local environmental conditions. These will of course vary, depending on the system and the location, but the batteries may be affected by especially high or low temperatures.

 

Conclusion

Regarding central battery back-up systems or self-contained emergency luminaires, the final decision on which type of system you choose will largely depend on the priorities for the system. Our team can advise you on the most suitable system for your project, contact us today for more information.