Reliable power for a sustainable world
What Do The Different Emergency Response Times For UPS Repairs Mean?

Emergency Response Times when there’s a fault or failure with an uninterruptible power supply should be clearly spelled out in the Service Level Agreement (SLA) of any ongoing UPS maintenance contract.  

The response time is triggered as soon as an issue has been reported, booked in by the service team and arrangements made for an engineer to visit the site and carry out the necessary repairs.  

Emergency response times categorised as Working Hours revolve around the working day, typically 8:30am to 5pm Monday to Friday. Any incident requiring a response outside of these core working hours, for example at weekends, will likely incur additional charges. 

In many cases, the decision for out of hours work depends on whether the UPS has maintenance bypass facilities or has been installed in a parallel-redundant configuration that can support a module being serviced without taking the entire UPS system offline.  

The majority of UPS maintenance plans offering a working hours response are categorised as 12 or 8 hours. In effect, the provision for both these sorts of coverage is a “next working day” response as a best case scenario.  

As the name suggests, Clock Hours response covers an incident at any time, not just those that occur in standard Monday-Friday office hours. Most UPS manufacturers provide emergency response on a 24/7/365 basis, with a response within 4 clock hours the norm. 

For the most mission-critical of sites, even faster response times (i.e. 1 or 2 hours) are achievable, particularly if crash kits of spare parts and common components are held onsite or at a nearby local service depot.  

With smaller UPS (i.e. below 3 kVA) a “crash kit” may actually constitute a full replacement of the unit, minus the batteries, as power supplies of this size only tend to have a couple of large fully-integrated printed circuit boards (PCBs).  

It is more cost-effective to supply in a replacement UPS chassis as a ready-made working model than to replace in the existing frame. 


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