Should You Repair or Replace An Ageing UPS?

They say that 80% of all uninterruptible power supply failures are down to a failed battery. This may be true in a lot of cases but simply signing off a replacement battery order my not be the right approach to get your UPS system back up and running.

There are several types of consumable components within a UPS system – not just the batteries. These other components within this most critical of power devices include fans and capacitors (AC and DC) in various quantities depending upon the type of UPS; transformer-based or transformerless. If you’ve ever seen a capacitor fire you will know the damage that thermal runaway can do to these components, even with a safety-disconnect cap. As a UPS system ages, there is also more chance that the internal electronics and wiring harnesses have suffered long-term heat damage. In some extreme cases, you can see this as cable insulation cracking or at least becoming brittle to the touch.

Should you worry? Well perhaps not in the early life of a UPS system (up to years 7-8) but what exactly is the expected working life of a UPS? A good guideline is ten-fifteen years with battery replacement taking place around years 3-5 or 7-8 respectively for a lead acid five year or ten year design life battery. I’ve always considered year 7-8 to be a good time to look at replacing a UPS or at least to do the budget calculations. There are several reasons for this. Firstly, this ties in with the average working life of the batteries. At years 7-8 you may have already changed a five-year design life battery at least once. For a ten year battery set you will be looking at a more costly replacement. The UPS industry also advances at a quite rapid rate over such a long time period with system prices failing, footprints shrinking, warranties extending and operating efficiencies rising.

If your UPS is 10 years old, it’s almost a no-brainer and the calculations almost always prove it. Up to time in a UPS systems operating life, battery replacement may well be the way to go if the operating environment is clean, dust free and within the recommended 20-25degree Centigrade ambient. All good aspects, that any good UPS maintenance company would identify during an annual preventative maintenance visit.

That’s the final point to note. If you have taken out a UPS maintenance contract make sure the UPS company providing the cover makes the preventative maintenance (PM) visit and where possible always add battery testing to the contract. There are too many UPS companies out there that neglect PM Visits until sites chase them up or a UPS alarms. I always recommend pre-booking PM visits when a UPS maintenance contract is taken out and have several FM clients who insist on this. It’s not just good practice but gets all the diaries lined up which can be especially important for out-of-hours PM work.

Not only will this help to prevent your UPS system failing into the ‘80% of failures’ data pool but with the addition of regular annual battery testing by the PM engineer, you can start to predict future battery performance and identify individual battery cells that weaken the entire set.

For more information on our repair and replacement services please contact the Eco Power Projects team on 0800 612 7388.