Knowledge Center


What is a UPS?

A UPS, acronym of Uninterruptible Power Supply, is an equipment that provides emergency power when the utility mains fails. It is equipped with batteries that start to work when the power outage occurs.

It also regulates the electric flux, reducing or increasing the different electric fluctuations and eliminating the bad harmonics of the means. It is an appropriate protection against power overvoltages, surges, spikes or brownouts.

These equipments are typically used to Project computers, networks, communication devices and any other electric device where an unexpected power surge or disruption could cause data loss or even very serious damages.

What is an AVR?

An AVR, acronym of Automatic Voltage Regulator, is an equipment designed to maintain a constant output voltage level, avoiding the typical voltage fluctuation of the utility mains. It regulates the electric flux, reducing or increasing the different electric fluctuations of the means, protecting the connected loads from power overvoltages, surges, spikes or brownouts.

Unlike UPS, AVR are not equipped with batteries, so the connected loads stop working in case of power failure.

How many types of UPS exist?

You can find three different types of UPS: Off-Line, Line-Interactive and On-Line.

Areas with few electric disturbances and good quality utility means.


An On-Line UPS, also called “double-conversion UPS”, is equipped with both an AC/DC rectifier and a DC/AC Inverter, and is continuously providing power from the batteries. That means that it is a real electric firewall for any sensitive device.

Any computer network, critical and essential (data networks, servers, telecommunications, industrial applications…)


What type of UPS should I use?

Depending on the quality of the electric mains available in your area and the kind of charge you want to protect, you can use the following types of UPS:

  • Off-Line UPS: Areas with few electric disturbances and good quality utility means
    Domestic applications or small offices.
  • Line-Interactive UPS: Areas suffering from voltage changes or unstable utility means, stormy periods
    Small domestic or office networks.
  • On-Line UPS: Areas with unstable utility means, with frequent electric surges, spikes, or power outages.
    Industrial applications, critical equipment protection.

What UPS capacity is the most suitable for me?

The Volt-ampere (VA) is the unit to measure the UPS capacity. It is also called “apparent power”. However, here you will also find the capacity measured in Watts (W), which is the real power, so you can easily decide which the most suitable UPS is following to your needs.

Here below you can find a chart with the estimated power consumptions of the most commonly used devices and systems.

Which is the maximum load a UPS can support?

Depending on the size and kind of UPS, different loads can be connected. The maximum load values are detailed on the datasheet, both in Watts (W) and in Volt-Amperes (VA). The load should not exceed 70%-75% of the maximum load value mentioned. Usually, manufacturers use Watts (W) to measure the power consumption of their devices.

It is important to take in account that laser printers should never be connected to a UPS as the current draw of a laser printer during start-up and printing can damage the UPS.

How long can a UPS keep running during a power outage?

The time while a UPS supplies backup power to the electrical appliances while power failure is called backup time. The unit of backup time is expressed in minutes and is applied for a load of 50% approx.

In case more backup time is needed, and as long as the charging system is up to it, more batteries can be added.

If the UPS already protects my devices, why do I need the software?

By installing the provided software on our PC and connecting the PC to the UPS through the USB or RS-232 communication ports, we get the UPS and our PC fully communicated. This way, we will be able to program the system shutdown and control all the UPS parameters, such as battery load, connected load, input and output voltage and frequency, etc. Not only can the UPS connected to the PC be controlled, but also the whole network. It even allows the remote control of the system via Internet. The software supports most of the current O.S.

In addition, some UPS have the option to connect a SNMP (Simple Network Management Protocol) Module, a system for managing devices on IP networks, used mostly in network management systems to monitor network-attached devices for conditions that warrant administrative attention.

Does a UPS need any upkeep?

Although the UPS does not need professional maintenance, it is necessary to follow some guidelines in order to increase its lifetime. Please, go to the maintenance section in this web.

What is the expected service life of a UPS?

Most UPS are good for at least five years. We advise you to change the batteries every three to four years. You must take in account that the battery lifespan is shorter when it is not being used, so, if your UPS is stored, we strongly recommend to charge and discharge its batteries regularly. With larger equipment, the lifetime of the equipment increases.

What is a Sealed Lead Acid (SLA) Battery?

A Sealed Lead Acid (SLA) battery, also known as a VRLA, Valve Regulated Lead Acid battery, has the following attributes:

maintenance-free, leak-proof, and not sensitive to positioning. SLA batteries are equipped with a safety vent to release gas in the event of too much internal pressure.

SLA batteries are used in many applications, such as home alarm systems, backup systems, generators, flashlights, spotlights, workout equipment, generators, motorcycles, ATVS, toys, and much more.

What are volts and amp-hours (example: 12V – 20Ah)?

Every battery two ratings: volts (V) and amp-hours (Ah).

Voltage is the measure of electrical voltage of the battery (there are many types of batteries, 2V, 4V, 6V, 8V, 12V, 24V)

Amp-hours are a rating of the amount of energy a battery can store.

Does my replacement battery capacity (Ah) have to be same as my original? How do I choose?

In some cases, where physical dimensions allow it, you can upgrade to a higher Amperage battery. For example, a device using a 12V 7.2Ah can use a 12V 9Ah for longer run time. Any bigger and the battery will physically not fit into the device, as the physical dimensions will be different.

The voltage of the original and the replacement has to be the same. In our example, a 12V 7.2Ah can be replaced by a 12V 9Ah for longer run time, but the battery must be 12V.

How long do SLA batteries typically last?

The majority of SLA batteries last anywhere from three to five years, depending on things like applications, charging method, and operating temperature. Most SLAs last 300-500 cycles.

Charge your battery before storage. Never store an SLA battery in a partially charged or discharged state. This will likely permanently damage the battery.

What is the shelf life of a sealed lead acid battery?

SLA batteries naturally discharge over time. If it is not charged periodically, the battery’s full capacity may not be reached again. SLA batteries self-discharge at a rate of around 3% a month. UPS Battery Center recommends checking on and charging SLA batteries every three months. Never store an SLA battery longer than six months without recharging it. Always store batteries in a cool, dry place. Generally, a battery can last 6 months to 1 year on a shelf at 25 degrees celcius.

What is “Memory Effect”?

SLA batteries do not suffer from memory effect. Never fully discharge any SLA battery.

Memory effect is also known as lazy battery effect; it occurs in some rechargeable batteries and causes them to hold less charge over time.
The original meaning refers to certain NiCd batteries which gradually lose their maximum energy capacity if they are often recharged after being only partially discharged. Batteries with this type of chemistry should be fully discharged before being recharged.

Sealed lead acid batteries do not have memory and function better when fully charged. The less often you discharge your sealed lead acid battery, the longer it will last. Never leave a sealed lead acid battery discharged. Always recharge after use.

My sealed lead acid battery is bloated or swollen. What should I do?

Immediately remove the swollen battery from the equipment it is in. A battery expands due to overcharging. High rates of overcharging will cause a battery to heat up. It accepts more current as it heats up, heating it up even more. This cycle of overheating is called thermal runway and it is able to destroy a battery fairly quickly, sometimes in only a few hours. It is all of the heat that causes the battery to swell.

The battery is not usable. Recycle it a local battery recycling facility. This battery needs to be replaced immediately.

How long will my battery run?

Battery run-time varies based on the power demands made by the equipment, as well as its capacity and run time. Every application is different. Contact the manufacturer of your device to determine how long the device will run with the specified battery.

What are “smart” and “dumb” batteries?

Smart batteries have internal circuit boards which allow them to communicate with the UPS or device to monitor performance, output voltage, and temperature.

Are the sealed lead acid batteries that you sell rechargeable?

Yes, all SLA batteries that we sell are all rechargeable.