Some of the latest UPS systems for telecom and mobile towers are compact, have inbuilt chargers, options for external as well as inbuilt batteries, are transformer free, and come in hybrid variants
For smooth running of a telecom setup and wireless network, there should be a reliable power infrastructure, as power management for outdoor and indoor telecom sites is vital. The requirement for UPS systems in the telecom sector can be broadly differentiated into two categories—active and passive. In the active IT category, power backup systems are required for base transceiver stations (BTS) or mobile towers, mobile switching centres (MSC), base station controllers (BSC) and tower sites.
The UPS rating for these requirements varies. For MSCs, the UPS power requirement is in the range of 120-160 kVA; for BSCs it is goes up to 40 kVA; and for towers, up to 10 kVA. Also, when the UPS system has to be installed on the tower itself, lower ratings of 1-2 kVA are required.
For passive IT application areas, the size of the UPS system required is bigger—400-600 kVA. Apart from these, AC and DC UPS systems are also required for mobile equipment.
What buyers should consider
So far, legacy UPS systems (centralised large systems) have been used widely. But the trend is changing towards the use of modular, scalable and highly energy efficient UPS systems with N+X redundancy, as well as remote monitoring and control for power management solutions. With such UPS solutions, one can scale up as the load grows, starting off with lower CAPEX (capital expenditure) and OPEX (operating expenditure). According to experts, double conversion online UPS systems are the right choice for the telecom sector.
In mobile towers, operators are more concerned about power saving aspects. Each tower has a transmitter, power supply related equipment, air conditioner, generator, etc. Buyers should carefully examine the power saving aspects of these backup gadgets since this function is linked to other important functions of providing mobile services, which are monitored by TRAI (like call drop, voice quality, etc).
Users should go for reliability, flexibility, durability and cost effective products. Manufacturers also offer innovative and tailor-made products and solutions to match the fast pace of technological changes taking place in the telecom sector. Solutions designed to protect equipment from downtime, damage and data loss due to power problems are the best choice. However, which power protection or management solution to choose; which player has the capability to customise, etc, are questions a buyer should consider carefully, as these products are quite expensive.
The trend is to move towards compact systems and rack based solutions to minimise the space required. As networks are becoming more complex, far flung and being managed from remote control sites, UPS systems need to be flexible enough to incorporate diagnostics and predictive failure analysis, and hence need to be equipped with multiple network management protocols. UPS systems for the telecom sector are now available with higher capacity chargers, add-on chargers and accessories that provide the user the capability to manage, diagnose and optimise medium to large battery bank installations.
The challenges of flexible capacity enhancements and lowest MTTR demands are best addressed by modular and scalable UPS systems. Buyers should go for products with features like a wide input voltage range, which helps to extend the life of the batteries; high energy efficiency, which results in lower wastage of electrical energy and cost savings for consumers; high power density and compact dimensions, which help in saving precious space, reducing rentals and ensuring better space utilisation.
What’s new in the market
To cater to the various applications in the telecom segment, Delta has recently launched the Amplon E/N/R single phase 1-3 kVA UPS system, which is designed for 48.26 cm IT/server and networking racks. The inbuilt high level charger shortens the recharging period. It is an online double conversion UPS system housed in a compact tower with external batteries for applications that require a long backup time. The Amplon N series single phase 1-3 kVA UPS system is also an online double conversion UPS system with the option of inbuilt batteries.
Last year, Delta had introduced the Amplon IN series single phase 1-3 kVA UPS system with an inbuilt isolation transformer, particularly for telecom applications in rural and remote areas where the quality of incoming power is poor and the electrical distribution quality is uncertain. Amplon IN provides galvanic isolated neutral to the loads, which gives full power protection to critical telecom equipment.
According to Suhas Joshi, director, sales, UPS systems, Delta Power Solutions (India) Pvt Ltd, the Amplon IN series is designed for short as well as long backup periods. The inbuilt high level charger cuts down the recharging time, and the high input power factor (IPF>0.97) and low iTHD save installation costs. This system comes with an LC display to provide detailed information about the UPS system’s operating conditions and electrical parameters like input/output voltage, load current, battery voltage and battery charge discharge current. This system has an inbuilt maintenance bypass that allows servicing of the system without interrupting power to the critical load. The Amplon IN can also operate at higher temperatures.
Emerson Network Power has also introduced a host of new power management products for telecom applications. The row-based Liebert APM is a transformer free, online UPS system that allows quick and easy capacity increases with no additional floor space. It has two models, the frame size of which can be expandable from 30 to 150 kW. These solutions are highly scalable and operate at a high power efficiency of 96 per cent.
The NetSure 710, a modular power system by Emerson, is ideal for wireless applications such as cell sites, co-location, large vaults or enclosures. It is simple to install and operate, and is also capable of remote access, allowing users to view, control and interact with the system using an Ethernet interface. “Emerson’s UPS systems for telecom applications come with the latest in UPS technologies that help remote access, and are capable of handling flexible loads. At the same time, we also aim to make our solutions easy to deploy and operate with the least manual maintenance,” says B Venkat Rao, country manager, medium and large UPS systems, Emerson Network Power. The Liebert APM, for instance, is bundled with FlexPower core assemblies that allow the system to expand in capacity or redundancy in 30 kW increments of up to 150 kW within a single cabinet. Addition or replacement of FlexPower cores can be done without powering down the connected equipment,” he adds. The NetSure 710 DC Power System, on the other hand, houses eight 3000 watt rectifiers on a single shelf, operating very well in high density wireless applications as it takes up minimum floor space.
To reduce costs while accessing round the clock power supplies, Emerson has developed hybrid power solutions, which are efficient in off- and on-grid environments. Emerson has also launched its high availability Inpulse inverter that acts as a secondary backup source and can substitute conventional diesel generators. “It provides hassle free operations as well as freedom from air and noise pollution. It also allows remote monitoring and the manual selection of batteries,” informs B Venkat Rao.
In May 2012, Su-Kam Power Systems Ltd introduced the Trusty-Mx single phase UPS system with a capacity of up to 20 kVA that has a 0.9 per cent output power factor, unity input PF and an LCD display. In the three phase range, it has launched the Multiplexer, one of the most reliable modular UPS systems, ranging from 10 kVA to 500 kVA.
“Su-Kam’s Multiplexer range has high power density and a small footprint. These systems incorporate a unique design in which all connections and cables are internal. The systems feature a galvanic true online battery connection (VFI), the lowest MTTR and minimal maintenance. This ‘green power’ system offers globally-certified clean and responsible energy technology to meet power requirements while minimising their environmental impact,” informs Gurdev Saini, general manager, UPS Systems, Su-Kam Power Systems Ltd.
Uniline Energy Systems has introduced two types of UPS systems—one with a DC rectifier plus battery bank for DC power, and another with an inbuilt battery for AC circuits. In this system, two sets of independent battery banks and two different boxes for the rectifier and UPS systems are required.
“In our hybrid UPS system, Uniline uses the 48 V DC operated system, where the DC power is directly fed to the DC load and a separate inverter is used for converting DC to AC. In this case, a common battery bank can be used for both AC and DC power, it requires less space and costs lower,” says RK Bansal, managing director, Uniline Energy Systems.
Companies also offer the use of solar power as an additional power backup alternative for mobile towers. Various operators are actively considering this option, as it is cost effective and sustainable. DB Power offers such solar PV power supplies and grid connect inverters. Adaptive architecture is a new technology in UPS systems, which offers features like modularity, scalability and higher efficiency. The battery-diesel-hybrid solution is another significant development in addressing energy OPEX, as well as the other challenges faced by telecom operators and infrastructure companies.
Today, most manufacturers offer customisation options, as that is the need of the hour. The latest UPS systems can be scaled up in terms of capacity, or the levels of redundancy can be increased when needed, by means of small, light weight, compact, hot swappable power modules that can be plugged into a UPS rack without the need for any additional floor space. Rectifiers or converters can also be added without changing settings or any other form of interruption.
Hybrid power solutions can be fine tuned at the time of deployment to minimise fuel costs, reduce capital investment, protect from unstable power quality, and minimise maintenance activities.
UPS systems also offer customised control and management solutions for providing information over mobile phones, LANs or any PC across the world. They can also ensure the remote control and management of unmanned sites by providing temperature, humidity, movement and other parameters of the UPS system.
Telecom companies demand tailor made and cost effective solutions. UPS brands are, therefore, making conscious efforts to keep the costs down. The costs of installation and maintenance for UPS systems are about 1-3 per cent of CAPEX in the first year and 3-5 per cent every subsequent year. However, the costs will also depend largely on the applications installed and the site conditions.
Keeping in line with the price competitiveness of the market, major players like Delta, Emerson, Su-kam, Uniline, etc, set their own prices. “Delta products contribute to a customer’s competitiveness significantly. Our UPS systems are very competitively priced despite being feature rich and coming with advanced specifications,” explains Suhas Joshi. For example, cost for products in the Amplon IN series range from Rs 25,000 –45,000. Su-Kam’s prices for UPS systems for telecom applications range from Rs 1700 for a 600 VA system to Rs 60 lakh for a 500 kVA system. Prices of Uniline products start from Rs 30,000 for a 2 kVA solution.
—By Srabani Sen