Why is true modular UPS the market standard?
Mon 18 Apr 2016
Shri Karve, senior technical consultant at Gamatronic, sheds some light on the merits of a true modular UPS system by comparing it with the basic modular system…
Over the past 10 years, many data centres have been installing true modular UPS systems that allow ease of scalability with a ‘build as you grow’ approach. Transformerless technology and ‘hot swap’ capability are some of the key improvements that allow manufacturers to offer compact modules that form a building block of vertical stackable system which can be extended.
A number of factors must be considered when choosing a UPS system in order to protect the load from disruptions relating to the mains supply. These are reliability, resilience, nature of load, power quality requirements, space requirement, future scalability and total cost of ownership (TCO). Correct UPS system scalability and sizing right from the outset is important to avoid issues related to future expansions of the data centre.
There seems to be some misconception with regard to true modular UPS system topology. It is therefore vital to differentiate between true modular solutions and a scalable parallel UPS system. Choice of module sizes and associated scalability requires careful consideration in order to meet the specific needs of the data centre with regard to CAPEX and OPEX at optimum level. Small incremental steps can provide better flexibility, less costly redundancy and offer higher operational efficiency reflecting in lower running cost when compared to UPS systems made of 200 to 300 kW increments. If a UPS system is made up of larger standalone individual units then there is a risk that the system input power factor may lead to lighter loads and much lower overall efficiency. Leading power factor can cause compatibility issues when supported by Genset.
Reduced floor space, lower running cost, improved reliability and resilience
Initial capital cost for a modular system can be more than that of a standalone system. However, this can be offset by the reduced operating costs due to its higher efficiency, lower infrastructure costs, low cost of maintenance/spares and superior availability.
In view of the above, it is better to utilise a true modular UPS system since these can be configured, and readily reconfigured, so they are operating close to capacity. Scalability of UPS system provides flexibility without sacrificing required redundancy.
Modular solutions provide higher operational efficiency compared to traditional standalone models because power demand and usage are closely linked and so there is no wastage due to over-sizing. This reflects in increased system efficiency and lower Total Cost of Ownership. Additional modules can be added to meet the increased load demand and still retain the initial planned redundancy. Hot swappable type modules improve availability to six nines (offering availabilities to 99.9999%) since maintenance and repair can be carried out with ease and can avoid any need for shutdown of critical load. Capacity of the system can be uplifted due to built-in incrementally within a true modular system to meet the demands of scalable data centres, without any disruption to service.
Let’s remind ourselves of all the benefits offered by true modular UPS systems. It is a greener solution due to high efficiency across wide load range. It offers flexibility and speed of future scalability within the footprint, as well as hot swap capability which increases availability due to improved Mean Time To Repair. UPS systems also offer reduced floor space, lower running costs, improved reliability and resilience.
This article first appeared in Data Centre Management – Spring 2016