Uninterruptible power supplies provide backup power, protecting equipment from damage in the event of grid power failure.
Please visit our website for more information on this topic.
An uninterruptible power supply (UPS) is a type of device that powers equipment, nearly instantaneously, in the event of grid power failure, protecting the equipment from damage. UPS systems vary significantly in their design and functionality, affecting the amount of time they can power equipment, their ability to improve power quality, and their cost.
Data servers, computer systems, industrial settings, and laboratories commonly use UPS systems. Because a UPS protects equipment, it is appropriate for any situation where electrical loads may be sensitive to power loss or other power quality issues. For example, UPS systems are commonly used for computers and servers because power loss to these loads may result in loss of data or component damage.
Likewise, many types of medical and laboratory equipment are sensitive to interruptions in power supply or poor quality power. For many health facilities in developing nations, grid power is unreliable or of poor quality, resulting in scheduled or unscheduled power loss for large portions of the day or fluctuations in grid voltage that may adversely affect equipment. In addition, power loss in hospitals and laboratories leads to downtime, affecting the quality and availability of critical services. Thus, health facilities often employ backup power systems to meet electrical loads in the case of power loss from the grid.
UPS systems serve two main purposes. They provide backup power as quickly as possible in the event of power loss, and they offer some degree of protection from power quality issues that may damage equipment. UPS systems fulfill these goals to varying degrees depending on their design and features, which ultimately affect their costs.
UPS systems provide a comprehensive, modular solution to protecting sensitive equipment from power supply problems. Depending on power quality issues to be addressed, three types of UPS systems are used:
Power quality refers to the adequacy of a power supply in terms of voltage, frequency, and waveform characteristics. Electrical equipment is designed to use electrical power with certain characteristics, such as 12 or 24 volts, or when designed for alternating current (AC) power, 50 or 60 hertz (Hz) frequency. Similarly, power supplied by the grid, or some other source such as a generator or battery bank, is intended to meet a certain voltage level or frequency. Typical issues associated with power quality include:
When selecting an appropriate UPS system for health facility applications, it is useful to have a basic understanding of the common terms and features that may be encountered when selecting UPS products.
Given the range of options for backup power and power quality equipment, selecting the most appropriate choice for a health facility requires a careful examination of the facility&#;s loads, power supply, and energy management capacity. Important questions to consider include the following:
The maintenance required for UPS systems is generally minimal. Battery health is the greatest concern in ensuring the overall effectiveness of a UPS system. Confidence in the UPS system&#;s ability to provide necessary run time depends on good battery maintenance. Maintaining UPS batteries entails periodic cleaning and testing as well as proper replacement at the end of the battery&#;s life.
USAID
Before investing in any energy technologies, a health facility must first understand its current day-to-day energy requirements. An initial energy audit is critical to ensuring proper system design and operation. Learn more
An energy audit helps develop an inventory and pattern of operation of energy equipment within a health facility, which enables the cost-effective planning and management of energy supply systems. Learn more
USAID
Batteries provide backup power during gaps in electricity generation. They are critical for some energy systems but are expensive and may require maintenance or replacement. Learn more
Timothy Quill (CC BY-SA 4.0)
Many organizations have established standards that address uninterruptible power supply safety, performance, testing, and maintenance. View the standards
This glossary of technical terms is designed to help you understand the frequently used terms within the uninterruptible power supply (UPS) industry.
A measure of actual power (Watts) drawn by an electrical load.
An electrical current whose electrons flow briefly in one direction to a peak before dropping back to zero and then flowing in an alternative direction
before repeating itself. The waveform created is a sine-wave.
A measure of the flow of electrical current.
The number of Amps that a battery set can deliver in one hour.
The electrical current drawn by a load at a given supply voltage measured in VA.
A measure of system up time compared to its downtime expressed as a percentage.
An electrical circuit incorporated within a UPS (or bypass panel) creating a power path from and to a bypass supply, which may be relay or static
switch-based.
A mains power supply voltage stabilisation device. Also known as an Automatic Voltage Regulator (AVR) or Voltage Regulator (VR).
The amount of time, stated in either minutes or hours, that a battery set or other power source will support the load.
A self-contained battery consisting of a number of individual and connected battery cells.
A small storage device for electricity within a battery block.
Comprises of a battery string or a number of battery strings.
Comprises of a number of battery blocks arranged in series to achieve a set Vdc and Ah rating.
A power cut or mains power supply failure, also referred to as an outage.
A high charge voltage applied to a battery set.
A transformerless assembly within a UPS used to step up the DC supply from a rectifier or battery set to the level required by an inverter.
A bypass that introduces a break when transferring a load from the output of a UPS to the bypass supply, or bypass supply to a UPS.
A drop in the normal mains power supply voltage, which can last from a brief period of a few cycles to days.
Not to be confused with Battery Management System (BMS). A centralised alarm monitoring system normally providing either a visual indication board, or a computer monitoring screen, both of which will
indicate the power status.
A method of containing liquid spillage from a system, for example, oil or diesel from a standby generator.
A secondary power path providing a power supply in case the primary one fails.
The ability of a circuit to store electrical energy as a charge. This is known as a capacitive circuit.
A type of standby power system used within emergency lighting, security and medical applications, the operation of which is similar to that of a UPS.
A type of precision cooling system widely used in mid-sized to large IT environments. Cold water is pumped from a Chiller to Computer Room Air
Handlers (CRAH) designed to remove heat from the IT environment.
A device used to continuously refrigerate large volumes of water.
A protection device against high surge currents. In the event of a high surge, the breaker will trip and cut power to the current.
The level at which a spike or transient protection device clamps the voltage down to a lower level.
High-frequency electrical noise generated by disturbances between the supply lines and earth (phase-to-earth or neutral-to-earth).
A type of ferro-resonant transformer.
The abbreviation for Computer Room Air Conditioning unit. A device that uses a self-contained refrigeration cycle to remove heat from the Computer Room and send it away from the Data Centre through some kind of cooling
medium, usually piping.
The abbreviation for Computer Room Air Handling unit. A device usually installed in a Data Centre or Computer Room that uses circulating chilled water to remove heat.
Spares stored on site to enable a fast emergency response to a system failure.
The mathematical ratio of the peak to the root mean square value of an AC waveform.
Electrical systems which directly affect the ability of an organisation to function and which must be kept operational during a mains power supply
failure.
Electrical equipment essential to the operation of the organisation and which cannot be allowed to fail, and must be kept running during any
interruption of the mains power supply.
The &#;volume&#; of electricity flowing in a circuit which is expressed in Amps.
The restriction of the amount of current that can be drawn from any point within an electrical circuit or UPS output.
The process of removing moisture from air.
Electric current, the electrons of which flow in a single direction only.
A short circuit or overload disconnection protection device that protects other devices from being damaged, and does not interrupt their operation.
The ratio of Real Power (W) to Apparent Power (VA) at the fundamental frequency.
A variation in wave form from a true wave shape.
The power factor produced by the harmonics from non-linear loads.
A system employed by an on-line UPS which feeds mains electricity into a rectifier/charger, and converts AC to DC. The DC then charges the batteries and also feeds the DC into an inverter which then converts the DC back to AC. This clean power then feeds the electrical equipment.
See Volt Free Contact.
The ability of a device to respond to a load-step change and deliver a stable output voltage wave form.
When a live component with mains power grounds to earth.
High frequency disturbance on a sine-wave which may be Common Mode or Normal Mode.
The extent to which an electronic device will tolerate and generate Electro-Magnetic Interference (EMI).
The production of an electrical potential difference (or voltage) across a conductor, situated in a changing magnetic flux.
A type of electrical noise that causes an electro-magnetic disturbance.
A signal contact on a UPS which will initiate a total UPS shutdown.
The speed of response specified within a maintenance plan for an engineer to attend site.
Equipment which will need to be kept operational, but can withstand a 15 &#; 30 second power interruption.
A resonant interaction between capacitors and saturable iron-core inductors which limits current flow. This principle is employed within Constant Voltage Transformers (CVTs).
A voltage regulating transformer using the principle of ferro-resonance.
A communications device that can receive and route calls through a built-in mobile .
A term used when charging a battery set at a steady voltage level.
A device used to convert kinetic energy into a standby supply of DC power for a UPS either in place of a battery set or to reduce the initial discharge during momentary interruptions.
An electrical device for changing the input frequency to a different output frequency.
A device that uses gases such as hydrogen, or other fuels such as methanol, to generate an AC or DC electrical supply. Can be used as a greener alternative to battery power or generators.
A separation of the input and output supplies to a device in such a way that energy flows through a field rather than through electrical connections.
A protection device consisting of an arrangement of electrodes in a gas within an insulating, temperature-resistant ceramic or glass case which
switches to a low-impedance when subjected to a spike or transient voltage.
A device that converts kinetic energy generated by combustion into electrical energy to provide an AC standby power source.
A device that uses combustion to generate electrical energy and to provide an AC or DC power source.
Harmonics are multiple wave-forms of the basic frequency. The basic frequency or first harmonic within Europe is 50Hz USA 60Hz.
Distortion of a mains power supply sine-wave from its fundamental frequency and wave shape.
A device which reduces the generated harmonic distortion, enabling a high power factor to be provided to its AC source.
The number of complete cycles per second of a waveform. Normal mains frequency in Europe is 50Hz and in North America 60Hz.
A rack enclosed architecture in which parallel aisles of enclosures are arranged with rack fronts always facing rack fronts and rack rears always facing rack rears. This ensures separation between cooling air in the &#;cold&#; aisle entering the front of the racks and warm exhaust air leaving the back of the racks in the &#;hot&#; aisle. Separation of cooling air and exhaust air results in higher cooling system efficiencies and the ability to cool higher power densities in the computing environment.
An abbreviation for Heating, Ventilation and Air Conditioning. Sometimes an &#;R&#; is shown at the end to represent Refrigeration (HVACR).
Short-circuit current.
Nominal current.
For more information, please visit hbcy.
The cable carrying the mains power supply into a building from the electrical substation and Point of Common Coupling (PCC).
The generation of an electro-motive force in an inductive circuit by varying the magnetic flux through it.
An IP number is often specified when referring to protection against both solids and liquids offered by enclosures around electronic equipment. The
first number refers to solid objects, one being the lowest and six the highest. The second refers to liquids, eight being the highest protection.
A high power switching device used in rectifiers and inverters.
The initial surge in current drawn loads, for example, to charge capacitive circuits.
Circuitry that converts DC energy to an AC output.
A communications protocol that creates a hierarchical structure (one master and several slaves) from a single RS-232 communication link,
similar to MODBUS.
A measurement of energy defined as one Watt per second.
A load in which the relationship between voltage and current is constant, based on a relatively constant load impedance.
This is an off-line UPS with an Automatic Voltage Regulator on the mains supply. This will adjust drops in the mains voltage back to the correct
voltage and also modify electrical surges and spikes.
The electrical equipment powered from a device.
Switching off non-essential equipment in order to increase the total runtime of the remaining system being powered by a finite power source.
A bypass supply which is used to power the electrical equipment during maintenance, which can be either internal or external to the equipment. Also known as a bypass panel or wrap-around bypass.
A bypass that makes contact between the primary (UPS output) and secondary (bypass supply) power sources before transferring the load.
A measure of reliability and the average length of operational time between failures. This can be based on monitoring a field population, or calculated for a system based on the known MTBF values of its components to a defined process and standard.
A measure of the average time taken to bring back a system to full operation following a failure.
A device capable of absorbing very high surge currents without damage to itself.
A communications protocol that creates a hierarchical structure (one master and several slaves) from a single RS-232 communication link, similar to JBUS.
Normally measured in decibels (dB) or (dBA). Noise may also be referred to as electrical noise in a circuit. This is a high frequency disturbance which
can disrupt electrical circuits.
Electrical equipment that can be dropped during a mains power supply failure during load shedding.
A load in which the relationship between voltage and current fluctuates based on alternating load impedance.
A form of high frequency electrical noise, that occurs between phase and neutral.
Also called a Standby UPS. A system where the raw mains power bypasses the UPS but allows the batteries to be charged. On mains failure the battery power takes up the load.
A UPS which is permanently connected to the mains, and will provide a
break-free supply if the mains fails. On resumption of mains power it will also deliver a break-free switchover back to mains power. This type of
system uses a double conversion system and is also fitted with an automatic bypass. The PowerPure RT is an On-line UPS.
A device that uses a short optical transmission path to transfer a signal between elements of a circuit while keeping them electrically isolated.
An American term used to describe a mains power failure, also referred to as a Blackout or power cut. Some people consider a voltage drop of below 80V as an outage, since most electrical equipment will not operate below this level.
Voltage higher than specified in a circuit.
A parallel UPS system where the total electrical demand is met by operating a number of UPS in parallel, without redundancy.
A type of UPS system where the total electrical demand is met by two or more UPS, in an N+1 configuration, sharing the load between them
equally. If one UPS fails the other is capable of supporting the full load.
A synchronising switch joining together two independent groups of parallel UPS.
Within Europe, single-phase consists of an AC sine-wave of 50Hz &#; 230V. Three-phase is divided into three equal sine-waves with a phase to phase
voltage of 415V. This gives the customer a choice of 230V or 415V mains input.
The ratio of Real Power (W) to Apparent Power (VA) at 50Hz within Europe and 60Hz in North America.
The point where mains power enters the building is connected to the electricity distribution network.
The cleaning of mains power, removing saga and spikes and smoothing the supply before onward transmission to electrical equipment.
A strategy which addresses the different methods whereby electrical equipment is prioritised and given protection against mains power failure
accordingly.
The difference between the actual energy consumed (Watts), and the Volts x Amps in a circuit. Power factor may be either lagging or leading the voltage.
The device within a piece of modern electronic hardware that converts an AC waveform into the various levels of DC required to power internal circuits.
A simulated sine-wave created in an inverter by a switching action which varies with time.
All electronic circuits generate an electrical noise known as RFI. These disturbances can be generated externally or can be created by a UPS.
RFI filters, when fitted, will protect sensitive equipment.
Mains power which has not been cleaned.
Wasted energy returned back to the incoming AC power supply.
A measure of the actual power (Watts) drawn by electrical equipment.
The time taken for the voltage to stabilize after a standby generator takes up the load.
A component part that converts an AC supply into a DC supply.
An assembly used within transformer-based UPS which converts an AC supply into a DC supply. This then powers the inverter and charges the battery set.
Control specification of an AC/DC output voltage.
The capacity of a power protection system potentially exposed to hazards to adapt, by resisting or changing in order to reach and maintain an acceptable operational level.
An undesirable AC disturbance superimposed onto the DC wave-form powering a device.
Abbreviation for Restriction of Hazardous Substances, Directive /95/EC.
Taking one half of an AC current cycle, RMS is the square root of the average values of all the squares of current and voltage.
An Uninterruptible Power Supply that converts kinetic energy from a flywheel into electrical energy to power electrical equipment.
A standard interface for synchronous and asynchronous communications up to 20 kb/s between two compatible devices (one driver and one receiver) over distances of up to 15m.
Similar to RS-232 but to a maximum transmission rate of 100Kb/s &#; 10Mb/s, up to ten receivers from a single driver and a distance of up to m.
Similar to RS-442 but with up to 32 drivers and receivers.
The amount of time that batteries connected to a UPS will support the electrical equipment attached to it after a mains failure. (Also referred to as Autonomy)
Decreases in power, below normal mains power, lasting several cycles.
Electrical equipment that is not critical or essential but requires a clean shutdown.
A method whereby the output of one UPS module is used to supply the bypass of another. If one UPS fails the other automatically takes up the load.
A device which acts as a buffer reducing the initial surge currents of severe surges and transients.
A communications protocol that allows hardware, on a network, with a TCP/IP connection, to be monitored and controlled.
A graphic depiction, viewed on an oscilloscope, of the wave-form produced by an Alternating Current (AC).
A single-phase supply consists of a single sine-wave at a fundamental frequency. In Europe this refers to a mains electrical supply of 230V AC.
The speed at which a UPS can synchronise output frequency with another AC power source, such as a generator.
A very brief large voltage increase on the normal AC supply.
A term used to describe the delivery of a stable electrical output voltage from a device under stable load conditions.
A solid state high-speed switch capable of transferring a load between AC power sources.
An Uninterruptible Power Supply incorporating solid state electronics.
Electronic components capable of storing an electrical charge which can supplement usage of battery power within a UPS.
Very short duration substantial increase of the mains power voltage.
A type of Power Supply Unit (PSU), most commonly found within computer, telecommunications and electronic devices.
Also known as Transfer Time. The delay between the load transference from one AC electrical supply to another.
An adverse condition whereby batteries dramatically overheat. Often caused by cells generating heat as they become fully charged and cannot be sufficiently dissipated into the ambient temperature.
A 400V/415V mains supply achieved by overlapping three single-phases, each 120° out of phase with each other.
An electrical component which is a semi-conductor switching device.
The total harmonic distortion introduced into a system compared to a normal sine-wave.
The total power factor including both distortion and displacement power factors.
Also known as Switching Time. The delay between the load transference from one AC electrical supply to another.
An electrical component used for changing voltages. It consists of wire wrapped around a core with insulated iron plates. Also used to achieve
Galvanic Isolation.
A very brief but severe voltage increase within the normal mains electrical supply. Damaging to sensitive electronic equipment.
An electrical component introduced into a circuit to attenuate brief voltage surges.
A multiple of the third harmonic in a waveform.
An extended drop in the specified voltage.
The process of continued heat removal from the IT Room or Data Centre during equipment failure or power failure to preclude thermal damage and
data loss due to equipment overheating.
A source of standby power capable of maintaining the electrical supply to connected electrical equipment for a specified period of time. A UPS
can also be used as a device for cleaning the power supply of sags, spikes and similar aberrations. See Power Sonic UPS Systems.
A device used when two separate groups of parallel UPS need to have their outputs synchronised.
A type of Lead-Acid battery.
A base unit of electrical force. One Volt will send one Ampere of electrical current through a resistance of one Ohm.
A unit or units of Apparent Power.
A pair of contacts used to make or break other circuits.
A measure of power which flows to electrical equipment.
A graphical depiction, viewed on an oscilloscope, showing the shape of a wave.
Waste Electrical and Electronic Equipment, Directive /96/EC
For more ups powerinformation, please contact us. We will provide professional answers.