Why should I worry about power problems?

Even small disturbances in the main electricity supply can cause damage to electronic equipment. Power problems can cause unplanned shutdowns and data loss. All these problems can cost your company a considerable amount of money.

How common are power problems?

A recent Power Quality Study revealed that the average computer system is subjected to 289 potentially damaging power disturbances per year.

How can power problems be avoided?

All essential electronic equipment should be connected to a voltage regulator, power conditioner or, best of all, a UPS. A UPS will maintain a steady supply of power irrespective of the mains supply quality.

Where the problems occur

Industry and Commerce

• Banks, money-brokers, stock market and finance houses
• Shipping, airline handling and warehousing
• Stock and inventory control
• Process control and materials handling

Hospitals

• Life support systems
• Hospital logistics and management
• Body and Brain Scanning Machines
• Blood analysis equipment and data storage

Essential Public Services

• Local Council/Government Offices
• Telecommunications and satellite links
• Defence installations
• Police, Fire and Emergency services
• Essential services – electricity, gas, water, etc

What does kVA mean? VA mean? 
The output of a UPS or Power Conditioning product is measured in volt-amperes or VA (output voltage x output current). The term kVA refers to kilo-volt-amperes or VA x 1000.

What is the wattage and VA relationship? 
Put simply, real power (watts)/apparent power (VA) = power factor.

Is an on-line UPS better? 
On-line UPS units provide better overall power protection to the load than off-line. This protection includes power conditioning, regulated voltage and frequency, and zero translation time to battery during a utility failure.

How do I size a UPS for my application? 
Multiply the voltage rating of the equipment by the current rating of the equipment to obtain a VA rating. The UPS must be rated to deliver at least this VA rating. See the "How to Size a UPS" section of our web site for more info.

Can a single UPS support more than one workstation or server? 
Yes, if the UPS is sized large enough for the application. Maintaining close proximity of the hardware to be supported is preferred to long distance electrical runs, which can cause unwanted ground current imbalances. Our technical staff is available to assist in the design of the electrical distribution.

How much battery run-time do I need?  
This can vary greatly depending on the critical load. Do you need just enough time to save files and shut down the computer, or is this a 24/7 site where no downtime is acceptable? For a typical PC or workstation, you need at least 5-10 minutes of battery backup to complete any work in process and gracefully shut down your system during extended power failure. For more mission-critical systems, extended run-time batteries or emergency generators are required. A JT Packard representative can help you determine the correct solution for your unique application.

How do I select the proper size unit?  
Sizing a UPS for a PC or workstation can be simple. As with any electrical device, a computer has a rating plate that will give the power consumption, usually listed as "amps".

A UPS is sized by VA, or Volt Amps. To determine the VA, multiply the amps by the 120 (volts) to determine the VA (Volts x Amps = VA).  Be sure to allow for at least a 20% growth factor.

Configuring a larger UPS is more complex with many more variables such as interaction between devices, different voltages, growth planning, and distribution. Contact a power professional at CPT for assistance.

How can it help me? 
A UPS has internal batteries to guarantee that continuous power is provided to the equipment even if the power source stops providing power. Of course the UPS can only provide power for a while, typically a few minutes, but that is often enough to ride out power company glitches or short outages. Even if the outage is longer than the battery lifetime of the UPS, this provides the opportunity to execute an orderly shutdown of the equipment.  
 
Advantages: 
1. Computer jobs don't stop because the power fails.  
2. Users not inconvenienced by computer shutting down.  
3. Equipment does not incur the stress of another (hard) power cycle. 
 
How long can equipment on a UPS keep running after the power goes? 
That depends on how big a UPS do you have and what kind of equipment it protects. For most typical computer workstations, one might have a UPS that was rated to keep the machine alive through a 15 minute power loss. If it is important for a machine to survive hours without power, one should probably look at a more robust power backup solution that includes a generator and other components. Even if a UPS powers a very small load, it must still operate its DC (battery) to AC converter (the inverter), which costs power.