September 25 , 2021
When it comes to UPS (uninterruptible power supply), you have to make a lot of important choices. If you get it right, you’ll have a precisely sized UPS system that will safeguard you for years. So, how do you go about selecting the best UPS system for your needs?
What is the role of a UPS system?
When the mains power supply is present, an uninterruptible power supply protects against a variety of power difficulties. Sags, surges, spikes, brownouts, and electrical noise are all common power issues. A UPS system can also protect you against short-term power outages and longer-term power outages by using a battery set, which can be built within the UPS or attached to an external battery pack. The battery will most likely be a maintenance-free VRLA (Valve Regulated Lead Acid) battery, while some systems now offer options of Lithium-ion battery as well.
The Various Types of UPS Available
In a datacentre, server room, or industrial facility, there are three primary types of UPS topologies (IEC 62040-3) that differ in the level of power protection they provide to their linked loads.
Standby/off-line UPS systems: provide elementary power protection and are typically confined to applications with a capacity of less than 1kVA. They are low-cost, low-spec devices that are commonly used in small IT and computer applications.
Line interactive UPS systems are classified as voltage independent (VI) and give a stabilised output with a battery power inverter that transfers in faster than off-line/standby UPS systems. Line interactive UPSs may need to be oversized or come with battery extension packs to reach the desired runtime.Line interactive UPSs are often used in systems with a capacity of 2 to 3 kVA.
Online UPS systems operate online and are classified as voltage and frequency independent (VFI). They have a continuous-duty inverter that generates a digital sinewave output. Aside from any internal faults, the quality and purity of this output is nearly always superior than that of the mains power source. Longer runtime battery pack alternatives and fundamentally more dependable power protection are available with online UPS. On-line UPSs come in single and three phase configurations (1/1, 3/1, or 3/3), and can be tower or rackmount, with parallel connections to scale up or provide increased resilience (N+X redundancy). For a single-phase UPS, the maximum typical size is 20kVA, while for a three-phase UPS, the maximum typical size is 40kVA.
UPS Load Sizing
Identifying all of the loads that require UPS protection is the first step in every UPS project.
Within a server room or data center environment, some of the equipment that need UPS protection are evident, such as UPS for computers, server rack or network file server.Other loads, such as network devices and any linked connectivity, may be less visible or are not that obvious.If those installations are not properly safeguarded by an uninterruptible power supply, the rapid development in Edge computing and Internet of Things (IoT) related connections will expose them to network operational and connectivity concerns.
The most common unit of measurement for UPS systems is VA, which stands for ‘Apparent Power.’VA is equal to the supply voltage multiplied by the number of amps drawn.VA is converted to kVA when measured in 1000 units.Most loads have an Amp rating, and we use 220Vac for a three-phase supply in India.
The calculation is based on summing the VA determined for each phase together.The ‘Real Power’ drawn by the load is defined as the number of Watts or Kilowatts (kW) that can be measured.
A comprehensive list can assist in estimating the amount of UPS system required, which Server Room Environments can confirm during a UPS site survey.
Standby Generators and UPS Systems
Once you’ve compiled a list of the devices to be protected and their sizes, you’ll need to prioritise them and determine how long you want to give protection in the event of a power outage.
When there is a power outage, some IT equipment, such as network printers, can be dropped automatically (known as load shedding), whereas more vital devices will need to wait through the outage or be shut down in a controlled manner.
There may be a local standby power generator that can provide power in an emergency.
Centralised or Decentralised UPS
As a UPS installation grows in size, it’s important to decide whether to use a centralised (single) uninterruptible power supply to support the entire installation or a decentralised method with many UPS devices. Besides, there are other factors that need to be considered for the choice between centralised and decentralised UPS use:
Modular UPS systems have been increasingly popular in recent years, thanks to the fact that various UPS manufacturers now provide this technology. A monoblock (mono-block) single uninterruptible power supply unit used to be the standard UPS system. Two or more monoblock UPS systems were linked in parallel if an installation required redundancy in the form of N+X or increased capacity.
Each reputed UPS manufacturer like Microtek, has its own standard module UPS size and standard frame size for modular UPS. The UPS frame may hold multiple UPS modules, which can be stacked to offer N+X resilience and growth capacity. Modular UPSs can be right-sized for immediate use while also providing for infrastructure installation to enable for future expansion via plug-in modules.
Microtek supplies a complete range of UPS systems for the server room and can deliver complete requirement list of yours. If you’d like to talk about your next server room or datacenter UPS project, please get in touch and we’ll guide you with the right UPS for Server Room.