What is a UPS battery/ a UPS system?
UPS means uninterruptible power supply. A UPS battery takes over the power supply for a short time if the primary power source fails. A UPS battery acts as a secondary power supply in the event of a power failure. There are no delays between switching from a primary power source to the UPS battery and there is a seamless transition.
Battery-supported UPS systems are the most widespread. These contain AGM batteries or lead accumulators, power converters and an electronic control system.
Power outages and voltage fluctuations are still a major problem, and pose great risks for hospitals, banks, data centres or signal boxes. A stoppage can mean that the system crashes, data is lost, irreparable hardware damage occurs or there is a production/operational standstill. In the digital age, data has become so important that a loss of it due to a disruption in the power supply is irresponsible.
UPS systems are used in the event of a disturbance in the power grid, which not only provides protection against power failures, but also protects the IT from inferior power quality. A UPS system also protects against voltage peaks and harmonics.
A UPS system that ensures a continuous and secure power supply is indispensable for many companies.
How does a UPS battery / UPS system work?
The UPS system constantly monitors the power quality in the utility grid to which it is connected so that it can step in if a fault occurs. A UPS battery takes over the power supply if the primary power source fails. While the UPS system functions like a modern security system for reliable power, in the event of a fault, the UPS battery it contains takes over the power supply.
In normal operation, the consumers are supplied directly from their supply network. The control unit monitors the power quality and reacts in case of fluctuations. The UPS system then switches to the internal battery and supplies the loads. The direct current is then converted back to alternating current before the devices are supplied, this happens without delay. The consumer receives a message about the interruption of the power supply and can act accordingly.
The UPS systems are simply inserted into the power supply line of the system to be secured and ensure proper functioning and, in the event of a power failure, provide sufficient time to finish work that has been started and to switch off the equipment correctly.
How long does a UPS battery last?
In an uninterruptible power supply, the UPS battery is at the heart of the UPS system. Unfortunately, this most important part in UPS systems is often underestimated. In order to guarantee an uninterruptible power supply, battery tests and timely battery replacement are essential.
UPS batteries serve as energy storage in the UPS system, usually have a capacity of 12V and, depending on the model, a different capacity output.
Manufacturers specify a service life for their UPS batteries, but this service life only applies under optimal conditions. The following points are important for optimising the service life of UPS batteries:
- Operating temperature: 20 °C to 25 °C is considered the optimum temperature for UPS batteries. Temperatures that are too high or too low can even halve the service life of the UPS batteries. Temperature fluctuations and high humidity should also be avoided.
- Charge / Deep discharge: The nominal capacity should not exceed 80 %, as UPS systems discharge the UPS batteries very quickly in the event of an interruption and thus considerably reduce the life expectancy of the UPS battery.
- Storage: UPS batteries should not be stored for longer than 6-12 months (see manufacturer's instructions). Storing UPS batteries for too long without periodic recharging (every 3-6 months) will reduce the life of the UPS battery and may result in faulty performance.
If you follow the rules, you can optimise the life of your UPS battery.
When and why should a UPS battery be replaced?
In most UPS systems, low-cost batteries are used. These are maintenance-free and sealed gas-tight. A chemical-physical process takes place inside the battery, which is also exposed to certain external influences.
As described above, temperature, charging and storage have an influence on the service life of a UPS battery. Furthermore, however, the operating mode, maintenance intervals, the number of discharge cycles and the duration of time during which the discharge has taken place also play a role in terms of the battery's service life.
Manufacturers specify the service life under the EUROBAT standard. EUROBAT 5 then means 5 years under optimal conditions. In the case of safety-relevant systems, the EUROBAT 5 battery should be replaced after e.g. 3 years as a precaution.
Batteries are subject to wear and tear even if they are not loaded. If the UPS battery is used in a well-functioning network and is not needed in this case, this can also have an influence on the service life. If the battery is charged and has been switched to a trickle charge state, the battery is kept at full capacity with a low charging current.
In the deep discharge protection area, a chemical process occurs whereby sulphation takes place on the surface, a crust forms. If the crust is too thick, the battery voltage can collapse in the event of a power failure and the UPS will no longer function as it should.
To avoid faulty performance in an emergency, a regular test run every six months is recommended. This can be automated in some UPS systems. The battery will thank you with a longer life.
Where are UPS batteries used?
UPS batteries are mainly used in hospitals, banks, control centres, computer centres or signal boxes. The main areas of application are:
- PC, server and IT rooms
- LAN node
- Telephone systems
- Cash register systems
- Surveillance systems, access control systems
- Emergency power supplies (e. g. emergency lighting)
- Alarm systems
The selection of UPS systems depends on the type of equipment that needs to be supplied. But the user's need for safety and the place of use also play an important role.
We would be happy to advise you personally on this topic. Please feel free to contact us here.