We offer facilities managers some top tips to avoid a battery meltdown during summer maintenance.
Ambient temperature is one of the most important factors that impacts the performance of both the uninterruptible power supply and its batteries.
Winter poses its own particular problems for facilities managers and site admins, with cold weather putting extra strain on the nation’s power grid.
But as we head into the height of summer, rising temperatures can be just as – or even more – damaging, particularly with reference to the UPS batteries.
Riello UPS Technical Services Manager Jason Yates speaks to Tomorrow’s Facilities Management (Tomorrow’s FM) magazine about why summer maintenance is essential.
Summer Maintenance To Avoid A Meltdown
Jason’s piece highlights several factors that can affect UPS battery service life. These include operating voltage and the frequency / depth of discharge.
But he focuses on the damage sizzling summer temperatures can cause. Sealed lead-acid (SLA) batteries – by far the most widely used with a UPS – operate at their best at a consistent temperature of 20-25oC.
Battery service life halves for every 10oC above this recommendation. During summer, temperatures in non-air conditioned site rooms could touch 40oC or even 50oC, so if that’s the case you’re drastically reducing your batteries’ lifespan.
Jason explains that most data centres or large-scale sites will have sophisticated air conditioning to ensure temperatures remain inside the safe limit. But for facilities managers that don’t have this luxury, simple good housekeeping can help reduce the risk of increased temperatures.
It’s recommended to install the UPS and batteries in a well-ventilated location out of direct sunlight and free of dust or moisture. FMs should also leave at least 10mm between each block of batteries.
This provides enough room for heat to dissipate and also takes into account the battery casing itself expands slightly as it gets warmer.
Test, Test, Test
Meticulous UPS battery maintenance is another core part of robust summer maintenance.
Our article outlines various tests facilities managers should carry out. These range from basic manual inspections, checking for signs of corrosion or swelling, through to a variety of more in-depth examinations.
These include:
Impedance testing: a non-intrusive method of building up a history of each cell over time. Achieved by applying an AC current and measuring the impedance in milliohms. Its advantage is that the batteries don’t need to go offline, but it doesn’t offer the most detailed assessment of condition.
Discharge (Load Bank) testing: a thorough examination of the batteries under normal operating and peak load. Demonstrates which cells hold the charge and which might require replacing. Its major disadvantage is it takes the batteries offline, although this usually lasts for less than 24 hours.
Partial discharge testing: a mix of the two options. Batteries are discharged by 80%, so you get a better indication than with impedance testing. But there’s still 20% capacity available if the mains is interrupted during the test and the UPS needs to operate from batteries.
