There are nine common types of power problems. The 3-5-9 concept clarifies what types of problems can be avoided with which solutions, and in which environment each solution is the most useful.
Series 3 for non-critical applications
A basic solution that protects non-critical hardware and data against three out of the nine power problems. These UPSs operate in standby mode.
1. Power Failure
2. Power Sag
3. Power Surge
Eaton Powerware UPS