No matter what you are buying it’s important to check the warranty terms and what they cover. For UPS systems the warranty can range from 1-5 years and not all of them allow for batteries failures directly.
For single-phase UPS systems the generally accepted warranty term is 2-3 years (24-36 months). The warranty will include the electronics, fans and capacitors as standard. Few will cover the batteries used and will simply pass-on any battery manufacturer’s warranty either at 100% or on a pro-rata basis. Sometimes UPS manufacturers offer warranty upgrades from 2-3 or 2-5 years and may include the batteries or not dependent on the design life of the battery used.
The most commonly used battery is a 5-year design life block. This will typically require replacement in years 2-3, The next available is a 10-year design life battery, requiring replacement within years 7-8 typically. 15 and 20 year design life batteries are also available. Just to be clear, we are talking valve regulated lead acid (VRLA) batteries here and not lead crystal or lithium-ion.
Temperature and battery life susceptibility is one reason why most UPS manufacturers and suppliers don’t offer comprehensive UPS warranties. Batteries life can substantially reduce when operated in high ambient temperatures. Ideally the temperature for a UPS should be in the range 20-25degrees Centigrade. As a rule of thumb for every 1 degree rise above 30degrees battery design life will halve. When you consider that the battery in most single-phase UPS systems is a 5 year design life type, that’s not long to go before failure if the ambient temperature is very high in years 1 and 2.
Three phase UPS systems tend to be offered with a shorter 1-2 year warranty period (excluding the batteries) and tend to be under maintenance contract; one reason why the warranty period is typically shorter than single-phase UPS systems. For the battery set, the battery manufacturer’s warranty applies or the UPS supplier may offer a warranty upgrade package.
Industry-leading manufacturers like Riello UPS provide a 3 year warranty if their UPS is supplied through one of their approved power resellers. Otherwise the Riello UPS warranty is 1-2 years (range dependant). The battery may be included in the longer warranty period dependent on the UPS size or if a longer design life battery is used i.e. a 10 year design life battery. Huawei is are another industry leading UPS manufacture. The Huawei approach is again different as they offer a 1 year warranty as standard with additional upgrades offered for 3 to 5 years through their ‘HiCare’ or ‘CoCare’ packages. Again batteries are excluded from this warranty unless a special agreement is made. Power Control offers a third alternative in that the company provides a comprehensive warranty including the batteries (100%) for a 3-year term as standard. All UPS manufacturers and suppliers will more than likely include a misuse/abuse clause re operational temperatures in their sales terms and conditions and offer a fully comprehensive 5-year (60 month) warranty upgrade path.
Battery failures inside the first few years of UPS operation are rare. As the UPS battery can represent a substantial cost if they require replacement, it is important to always check how they are covered in the warranty. I’d also check the battery brand proposed. When it comes to critical power, the quality of the battery is just as important as the quality of the UPS system you install. When the mains power fails, your battery is your only instantaneous source of stored energy and one that you must be able to rely on.