Over time both AC and DC capacitors age, suffering from a deterioration of materials due to usage as well as from ambient conditions such as heat internal to the UPS module. As a result they become less effective and start to fail. As capacitors fail in a ‘capacitor bank’ those that remain must work harder and therefore they too start to fail. When the caps fail they typically ‘pop’ a safety valve and can start to leak oil, in extreme cases they can rupture.
Experience has shown that AC and DC capacitors should be replaced, just like batteries before they fail, typically every 5 years and in some cases a little more frequently.
UPS Warehouse Ltd have both the experience and the necessary capacitors available when you need it.