From what we've seen so far this season, it sure looks like this summer is going to be a doozy for storms. We've had a few blackouts already and quite a bit of rain with accompanying thunderstorms. We've only lost power here at the office once, and we happened to be onsite earlier this month when a client site lost power for around 90 minutes.

The picture to the right was taken at Redcliffe on October 26, 2003.  The full story can be found here.

Power problems can present in a number of forms, mainly surges, spikes, sags, brownouts, blackouts and noise, and all of these can cause varying degrees of damage to your sensitive electronic equipment (and worse - to the data stored on your computer systems). There are a number of different products available that can help to protect against these problems, and both your budget and the value of the systems and data to be protected will determine which products are most suitable for your situation.

Surges
A power surge is generally accepted as being a voltage increase of up to 500V that lasts around 2 seconds or less. These can be stopped by mains filters and many UPSes as well as voltage regulators. Surges can damage your equipment by running the power supplies over their rated maximum voltage, causing breakdown of the power supply itself, and also increased output to the internal components (for example, the +12 VDC output may run at +20 VDC, destroying sensitive components. This is even more critical with +3.3 VDC components and those running at even lower voltages, such as RAM and CPUs.

Surges can be silent killers.  Well, killers of components.  It us usually obvious when a power spike has occurred - your light bulbs can explode, or a lot of equipment may fail.  Surges, on the other hand, damage components in some equipment and not others, and a number of small surges may be needed to cause sufficient damage to cause a component to fail.

Spikes
While power spikes run for significantly shorter times than surges - typically less than a few milliseconds, the voltage can be much, much higher. Spikes of up to thousands of volts are common when transformers explode, cars strike power poles, and lightning strikes nearby. A direct lightning strike is likely to cause total destruction of all electronic equipment, possibly even some that is not connected to mains power. Spikes can be limited by surge suppressors, but direct lightning strikes are likely to cause your building to burn down and the electrical wiring to explode. Smaller spikes are also caused by fluorescent lights, electrical motors and fridges. These are all limited by the use of a surge filter.

I have seen buildings where the power cabling has been blown through brick walls by direct lightning strikes that caused massive power spikes.  There's not much that can protect against natural phenomena of this magnitude.  However, smaller spikes can be almost as damaging to your equipment - a fried hard drive with all of your critical data on it can bankrupt a company as easily as a fried server rack.

Sags
A power sag can occur when a nearby large load (such as a welder or air conditioner) is started. A sag usually lasts only a few cycles (and in Australia we run at 50 cycles/second) and at a voltage from just under to about half of the normal voltage (240 Volts for single phase power in Australia). An undervoltage like this can cause equipment damage through power supply overheating and unstable power supply output voltages. Data can be damaged as a result of unstable output voltages as well as the possibility that the power supply will shut down momentarily if the voltage becomes too low.

Brownouts
Similar to a power sag, a brownout occurs when the voltage from the power company is reduced for a long period of time. This can occur if the load required exceeds the load the power company can deliver (this happens during peak load times) and also when a very heavy load is used (such as during building work). Brownouts can cause similar equipment and data damage as sags, but due to the longer nature of brownouts, the likelihood for damage is greater. Both sags and brownouts can be circumvented by the use of an appropriate UPS. There are a number of different types of UPS, and these are discussed here.
 
Blackouts
A complete loss of power is known as a blackout. Unfortunately, Brisbane (and South East Queensland, in general) being where it is, we're more than likely to be affected by blackouts over the next few months in particular. An adequately sized UPS is the only way to ensure that short term blackouts (10 minutes and less) don't affect your servers and their critical data. If the blackout lasts longer than this, then the UPS software will initiate an automated shutdown before it has completely exhausted its battery reserves. You could, of course, use a generator to restore a power supply before the UPS runs out of batteries, but most Small to medium enterprises don't have the funds, nor the need to go to this extreme. If you do need to hire a generator during an emergency, Quark IT can arrange this for you and ensure that your equipment is connected correctly and safely.
 
Noise
In theory there should be no noise on the power lines - a clean, pure AC sine wave is what should be hitting the power connector on your equipment, with the "ground" being at 0 volts. Unfortunately, this is not always what happens in reality. Noise can cause various issues with equipment, especially home theatre equipment, but also equipment that is connected to serial (RS-232) devices and to equipment in other buildings. Ground loops can cause audible hum in home theatre equipment and also data loss in computer equipment. There is no easy way around a lot of these problems, but through a thorough investigation of the equipment involved, a plan can be designed to reduce the issues to below a safe threshold.


Quark IT can supply surge suppressors that have been designed for Australian conditions. The Surge Shield range of mains surge suppressors from Thor Technologies offer industry leading protection for your sensitive electronic equipment - from home computers and home theatre equipment to your business desktops and servers.
 
With access to the full range of UPS products by manufacturers such as Thor technologies, American Power Conversion (APC), Powerware (Sola), and others, Quark IT can offer a solution for every situation - from a desktop to a data centre!

There are various other products such as the APC Line-R voltage regulators, telephone line surge protectors, notebook surge protectors and network surge protectors that can be used to provide a further level of safety and protection for your equipment and data. Feel free to contact Quark IT to discuss power protection options to suit your needs.


Protection:

Uninterruptible Power Supply (UPS) Definitions
There are many varieties of UPS, but these are divided into four main types: Delta Conversion Online, Double Conversion Online, Line Interactive Standby and Offline Standby.  The reason to choose between these comes down to security (which one makes you feel better), reliability, efficiency, and your hip pocket.

All UPSes have the same basic components - mains input (from the utility supply), battery charger, battery, inverter, transfer switch, and mains output (to the protected equipment).  The routing of power inside the various UPSes is what determines what type of UPS it is.  Many UPSes also contain surge supression and noise filters.

Offline Standby UPS
With an Offline Standby UPS  (sometimes referred to as simply a Standby UPS), the mains power drives the battery charger, ensuring the battery is always ready for action, and the mains power is also used to power the protected equipment.  When the mains voltage drops below a specified threshold, the transfer switch routes battery power (via the inverter) to the output so that the protected equipment runs on battery power whilst the mains input voltage is insufficient.  The typical switching time from mains to battery power is normally less than 5 ms (5 thousandths (or 1/200) of a second) which is much faster than a single AC cycle (1/5 of a second).  This means that normally your protected equipment will not even notise the change over.

Line Interactive Standby UPS
A Line Interactive Standby UPS (also known as a Line Interactive UPS), like a Standby UPS, runs the protected equipment from the mains supply unless there is an anomaly with the input voltage.  The main difference between the two is that a Line Interactive UPS uses "Automatic Voltage Regulation" circutry so that if the voltage is only a little under the normal voltage, the battery supplements the mains voltage to provide the required output voltage to your protected equipment.  This reduces the need for a complete switch to battery, resulting in a reduced switching time (as the battery is brought online whilst the mains power is still supplied) and also less drain on the battery, prolonging the "run time" of the UPS.

Double Conversion Online UPS
The main difference between the Online UPS and the Standby and Line Interactive UPSes is that an Online UPS is always using battery power to supply its protected equipment, resulting in zero transfer time.  This means that the batteries are always in a state of partial charge, but there's no chance that the transfer time will affect the protected equipment.  This type of UPS is the most expensive UPS available, and is generally used to protect large servers, data centres and critical equipment (such as medical and banking equipment).  Due to its constant use of battery power, it is also the most inefficient UPS, and generates the most heat.

Delta Conversion Online UPS
The last type of UPS - the Delta Conversion UPS is the most recent type to hit the marketplace.  The Delta Conversion UPS takes the best features of the Line Interactive UPS and the Double Conversion Online UPS and combines them so that the protected equipment is constantly powered from the battery supply, with a "top up" (or Delta) being supplied directly by mains power.  This results in a UPS with zero transfer time, greater efficiency, and reduced power consumption.