If you’re reading this, there’s a strong chance that you already have an idea of what a UPS is. I’d imagine that phrases such as ‘disaster recovery’, and ‘emergency power’ are flashing through your mind right now.
And you know what? You’re half right.
UPS systems do provide emergency power in the event of an outage, either to enable the safe shutdown of your equipment, or as a stopgap until generator power kicks in.
The trouble is, not only do UPS systems have another (more important) role, but if you’re only considering implementing a UPS on the basis of disaster recovery, it probably won’t happen until it’s too late. You see, as a species we’re terrible
at assessing risk
But more on that later. For now, let’s consider what a UPS actually is.
More Than Just Emergency Power
A UPS, or uninterruptible power supply, is a device that sits between the mains power supply and your critical systems, performing two primary functions:
1. Providing emergency power in the event of an outage
2. Filtering disturbances from the mains power supply to provide safe, clean power
Disturbances? What disturbances?
Well as it happens, outages are not the only thing that can go wrong with your mains power supply. Here are some of others:
· Spikes– Short, rapid fluctuations in voltage, ranging in intensity from a malfunction at the power company to a locally grounded lightning strike
· Electrical noise– A ‘catch-all’ term for interference in the power supply lines, which might be caused by load switching, cable faults or radio frequency interference (RFI)
· Surges– A sustained voltage increase, usually occurring after a large load is switched off
· Sags– A drop-off in the mains supply, usually occurring when a large load is switched on
· Brownouts– Identical to sags, but with much longer duration; these occur when the mains supply is unable to cope with the current load demand
· Harmonics– Current and voltage distortions caused by loads such as computers, photocopiers and laser printers, which pull current from the mains supply in large peaks
Power Outages: A Red Herring?
OK, so there are plenty of things that can go wrong with the power supply, and in fairness many people are aware of that. The problem is that these minor fluctuations are often more damaging to your equipment than a complete outage would be. It’s easy to imagine the implications of an outage on your organisation – Loss of business, inability to trade, data loss or corruption, and so forth.
But did you know that temporary, generally unnoticed fluctuations in your power supply often do far more damage to your equipment than outages? The phenomena described above can easily result in a reduced lifespan, or even failure of your critical systems.
But what does all this have to do with risk assessment?
If you read the Schneier article linked earlier – and I suggest that you do – you’ll notice that he highlights the tendency for people to worry about spectacular (but rare) risks whilst ignoring far more likely ‘mundane’ risks.
In the UK the average time between mains power failures is 10,000 hours, or 445 days. By contrast, the average time between disturbances is as low as 50 hours in some areas. Combine these figures with the damage caused by disturbances, and we find that outages are not only by far the least frequent of power issues affecting your systems, they’re almost always the leastexpensive.
Clearly, then, it doesn’t make sense to consider UPS systems purely on the basis of protection against outages.
Protecting Your Business
Hopefully this article has helped to explain what a UPS is, as well as putting the various risks averted by UPS systems into perspective. The headline that you’ll still be able to work (or at least safely shut down your equipment) in the event of an outage is a good one, but I can’t emphasize strongly enough the importance of protecting your business against power disturbances.
If you’re running a small business, UPS Ltd. offer a range of strong, single-phase UPS systems
which are designed to provide small scale critical power protection for computers, small-medium sized server rooms, network hardware, telecommunication systems, CCTV and more. These systems will protect your equipment every day from the impact of harmful disturbances in the mains power supply, and – of course – in the event of an outage they’ll enable to you safely shut down or transfer to emergency power.
Don’t get me wrong – defence against power outages is very valuable, and if you’re constructing a business case for implementing a UPS system I wouldn’t blame you for using it as a major argument.
But when you come to the cost/benefit analysis, it’s vital to include the impact of power disturbances – Quite simply they’re much more common, more damaging, and more expensive.