Why is UPS technology unreliable? [closed]

manpreet Best Answer 2 years ago

Following the UPS issue at SO today I recall my experiences with UPS (uninteruptable power supply) systems in the work place.

Typically we would arrive at work in the morning and find all systems out. There was a power outage and the UPS failed to work correctly. In fact I can only remember one time when a UPS actually worked. That's a pretty poor track record - though of course my own experiences may be just unfortunate and UPS systems in reality are as reliable as having two slices of bread at opposite sides of a cheese sandwich.

EDIT The original question may invite opinion based answers. Apologies - my question is rephrased now as:

What factors can cause UPS systems to fail? What are the limitations of UPS?

manpreet 2 years ago

To directly answer your question, not if they are good quality, used properly and within spec.

I have not had bad experiences with UPSes when they are used properly. Much of this depends on your specific situation. While IMHO the way you have worded your question invites extended discussion rather than precise answers and might be considered a poor fit for Superuser's Q&A format, there are some definite non-argueable points that one should consider when relying on UPSes.

• Are you using name brand UPSes?

• Are they new? Buying used UPSes is generally a bad idea.

• Is everything connected under the wattage limit for the UPS?

• Are you in an area with poor quality power or lots of storms? Those can shorten the life of any UPS.

• Desktop UPSes are generally meant to give a system 15 or 30 minutes of uptime to allow for clean shutdown. Solutions that keep an entire datacenter running are typically diesel run generators and things like that. Are your computers configured to shutdown when the UPS is low on battery?

• Batteries and UPSes wear out and must be refreshed periodically. So if you have a system on a 5 year old UPS it might not be as reliable as a new one.

• If you are depending on UPSes as part of a business continuity plan, you really should buy a few, connect them, configure them properly, and then test them to be sure they will work according to your expectation. Rolling out something like this without a testing phase to confirm may lead to a bad time.