What is a UPS? (Uninterruptible Power Supply)

What is a UPS? (Uninterruptible Power Supply)

So, what is a UPS, orUninterruptible Power Supply? An Uninterruptible Power Supply is a device thatis used to keep computers and equipment safe when there is a loss, or a significantreduction, in the primary power source.

To achieve this, the UPS housesseveral batteries that take over when it detects a loss orreduction in available power.

Once this is detected, the controlis transferred over to the batteries, and via an inverter, the batteries DC voltageis converted into AC for the devices.

In reality, it doesn’t have to be computerssystems and equipment that are kept alive by UPS.

It could be anything from afish tank, to a foot massager! We aren’t just talking about plain poweroutages, lights off, TV off, everything, but we can sometimes get spikesin power where a sudden drop can assure our devices are momentarily poweredoff, or something known as a brown-out.

This is where there is a voltage drop,either unintentionally, or intentionally. Sometimes in an emergency, there is aload reduction, caused intentionally. With a UPS, all of oursystems can run as normal to compensate for thereduction in power.

The amount of time the UPS cansustain a system for can vary, but it allows the opportunityfor the issue to be resolved, or at the very least, allows for the systemsto be shut down in a controlled manner.

Even the simplest UPS is madeup of a number of parts. We’re going to look at the standard partsthat you can find in a basic UPS system; Since a UPS is a system thatuses batteries to power a system should the supply be compromised, we, ofcourse, have batteries and a battery charger.

Since the batteries use DC current andour incoming supply is AC current, we need to convert DC to AC using an inverter. Finally, we need a way of switching betweenthe AC incoming supply and battery power.

For this, we use somethingcalled a transfer switch. So, to break it down, these are theparts we need for a basic UPS system; Batteries, Battery Charger,Inverter, and Transfer Switch.

A UPS provides second level surge protection, but although it does provide some protection, it should usually be used alongsidean adequate Surge Protection Device or SPD to extend the life of the UPS aswell as the attached equipment. Sounds simple, right? We’ve already discovereda basic UPS system and what parts it includes.

Now, we’re going to find out all about thedifferent types of Uninterruptible Power Supplies and what their typical functions are. Firstly, and the most common in smallersystems is the Standby or Offline UPS.

This is the one you would normally useon a personal computer for example. The Standby UPS lays in wait forits time to spring into action, and once there is a power failure, it takes control. The Standby UPS tends to be themost cost-effective UPS available.

Next up, we have the Line Interactive UPS. You’ll find this type of UPS insmall business infrastructure. It is very similar to a Standby UPS but with theadded ability to regulate voltage automatically.

This means that it monitors the incoming supply and can help out if it detectsthat the voltage is a bit low, or a spike is causing it to go too high.

It can add or subtract power in this way to make the output to ourdevices constant! Very smart! This type of UPS is particularly useful for thebrown-out situation we’ve already mentioned, or power spikes or surges.

Now we have the Online Double Conversion UPS. Don’t let the name put you off, this type of UPSis efficient as the primary source of power Isn’t the incoming supply,rather it is the battery power.

So when we have a power outage, thereis no transfer switch to close, meaning no time to switch that youcan get with the other type of UPSs. When the incoming supply is ON,the batteries simply charge up.

It’s called a double conversion becauseit converts the AC incoming supply to DC, and then the inverter convertsit back to AC for the output. In general, it ensures a far higher degree of isolationof the load from the irregularities on the mains supply.

These are the most commontypes of UPS available. Of course, there are other types thatfit a particular form or function, but these tend to be for more specialist needs. In summary, today we’ve learned aboutUninterruptible Power Supplies.

We’ve learned that they can beused as a backup to mains power in an emergency situation such as a power outage. More advanced UPSs can regulate thevoltage to prevent damage to equipment in case of a brown-out or a power surge.

We now have a good understanding ofwhat parts are used to make up a UPS; batteries, a battery charger,inverter, and a transfer switch.

Finally, we know that an Online DoubleConversion UPS is the most efficient as it doesn’t need a transfer switch as the primarysource of the power goes through the batteries! I hope youenjoyed learning about UPS systems, why we use them and what they are used for. Ok, that’s all for today.

About: AbbasSheikh