Selecting an Uninterruptible Power Systems - ITEC S.A.L.
Selecting an Uninterruptible Power Systems

Uninterruptible Power Systems

Power Quality "Even in the US, where power quality is relatively good, a typical computer installation experiences each year an average of 289 power disturbances potentially harmful to sensitive electronic devices."*
* Five-year study by Best Power National Power Laboratory

Power Disturbance Study

  • Monitored 130 sites throughout the US

Disturbances - any power aberration outside the recognized susceptibility limits for computer equipment, as established by the Computer and Business Equipment Manufacturers’ Association (CBEMA)

.The average computer … is buffeted by the following over the course of a year:

    • 16 power blackouts
    • 164 surges/overvoltages
    • 90 sags/undervoltages
    • 19 transients or spikes

.Power Blackouts - Power is out for more than 8.35ms

Surges/Overvoltages - Usually caused by drops in electrical demand and widespread equipment shutdown.

Sags/Undervoltages - Caused by large loads starting up, line faults in utility power, or rolling brownouts created by utility companies on peak-use days.

Transients or Spikes - Most caused by lightning, some by power coming back on after a blackout.

"The 5 Most Unwanted" power problems and why you need to arrest them

1) Power Failures - hard drive crashes, data loss, prolonged downtime.
2) Sags - workstations and servers freeze, hard drives garble data or misplace it, and motor parts wear out faster.
3) Surges - electronic wear out, equipment fail prematurely
4) Spikes - cause aborted modem transfers, microchip failures, fried hardware.
5) Electrical Noise - harmonics, electromagnetic interference, and radio frequency interference. Created by neighboring office equipment or machinery on the same power line. Corrupts data and causes "glitches".

Questions on power protection

    • What kind of power protection?
    • How much protection?
    • Do you need power backup?
    • How much backup time?
    • Do you need uninterruptible power protection?

Types of Power Protection

- Depending on the problems you are experiencing (or expect to experience) you should have one of the following items protecting your important equipment:

    • Surge Suppressors
    • Power Conditioners
    • Uninterruptible Power Systems
      • Basic UPS (Standby Power System)
      • True on-line UPS
      • Advanced UPS

    .

  • Surge Suppressors
    • Protection from surges & lightning
    • Hi-speed protective fuses protect against catastrophic spikes
    • Usually 15 - 20 amp capacity
    • AC line and data/telephone lines

    .

  • Power Conditioners
    • Comprehensive voltage regulation and isolation from non-continuous applications.
    • Controls sag & surges.
    • Isolates equipment from high frequency and other noise.
    • Spike attenuation for defense against lightning.

    .

  • Basic UPS
    • Lightning and surge suppression
    • Back-up power (minutes)
    • Battery management
    • 280VA to 1000VA
    • Generally what is advertised in computer magazines in the $100 range.

 

  • True on-line UPS
    • No Break Power
    • True Sine-wave Output
    • Battery Management
    • Brownout Boost Voltage
    • Excellent Lightning and Surge Protection
    • Diagnostics

 

  • Advanced UPS
    • Uses specialized transformers for providing clean, consistent, no-break power
    • High efficiency
    • Filters non-linear loads
    • High-line protection
    • Brownout Protection
    • Lightning Protection
    • Galvanic Isolation
    • No-break transfer
    • Long Backup

Ten Easy Steps to Selecting a UPS

1) Make a list of all the equipment you want to protect

2) Identify the power usage (see manufacturer's equipment label)

 

3) Add up the VA of all equipment

 
4) Calculate a 25% growth factor (* 1.25)
Example:
498VA
x 1.25
= 622.50 VA

5) Select a UPS size according to your VA requirements
Example:
650VA UPS or higher

6) Determine how long you will need backup of your process before you are able to shut if off or power is restored.
- 10, 20, 30 minutes plus (The longer the back-up time, the larger the batteries and the costs)

7) Choose the size of back-up batteries you will need at full-load (All of you equipment running at full power)
Example:
10 minutes Full-load/29 minutes Half-load
15 minutes Full-load/35 minutes Half-load
20 minutes Full-load/41 minutes Half-load
30 minutes Full-load/52 minutes Half-load
 
8) Select a UPS that meets both your VA and battery back-up requirements
 
9) Enjoy the benefits of UPS power protection