Power quality problems are common and can come from a variety of different sources. The definition of power quality is simply the interaction of electrical power with electrical equipment. If electrical equipment operates correctly and reliably without being damaged or stressed, we would say that the electrical power is of good quality.

On the other hand, if the electrical equipment malfunctions, is unreliable, or is damaged during normal usage, we would suspect that the power quality is poor.

As a general statement, any deviation from normal of a voltage source (either DC or AC) can be classified as a power quality issue.

Power quality issues can be very high-speed events such as voltage impulses / transients, high frequency noise, wave shape faults, voltage swells and sags and total power loss. Each type of electrical equipment will be affected differently by power quality issues. By analyzing the electrical power and evaluating the equipment or load, we can determine if a power quality problem exists.

Most power quality problems are related to issues within a facility as opposed to the utility.  Typical problems include grounding and bonding problems, code violations and internally generated power disturbances.

One simple example is powering different equipment from the same power source. If running equipment that generates neutral-ground voltage swells and line-neutral voltage sags then this can cause issues with other equipment that may be powered from the same source. A simple example is printers that have similar power characteristic results mentioned.

Today’s data centers are growing in their need to remain available. Financial, medical, government and any other organization that heavily rely on transactions or communication all demand less than one minute of downtime per year or available 99.9999% of the time.

Combine this with newer equipment that is extremely sensitive to power quality variations and you have a recipe that demands you pay close attention to your power quality.

Power problems can create big problems for corporate data centers. The result can be damaged equipment, lost data, corrupted data or even risk of fire or life safety. Engineers and facility managers should all take special precaution and understand the causes and effects of power problems.

The first step is to look to a guide. The IEEE 1159 standard or IEEE Recommended Practice for the Transfer of Power Quality Data is a great start and is the U.S. standard for categorizing power quality disturbances.

Stay informed and educated. Work with a qualified professional who can assist and help you to develop your own checklist to troubleshoot power quality problems.

Some simple questions to ask yourself and to help you determine if you are at risk include:
Are you experiencing?
1. Erratic computer operation?
2. Keyboard lock up?
3. Network Data Errors?
4. Hard Drive Failures?
5. Frequent monitor failures?
6. Power supply failures?
7. Motherboard failures?
8. Network hardware failures?
9. Lightning damage?

These are only some of the visible issues you may experience due to power quality issues. In many cases you may never see one of these issues occur, but one or more may be lying in waiting.

The following are some simple and certainly not all inclusive recommendations:
1. Be sure that each computer connection or electronic branch circuit should have individual phase, neutral, and ground conductors.
2. The data center and print functions should not be located together nor should they share the same power source. Connect laser printers and heavy duty copiers on individual 20 Amp branch circuits.
3. When making upgrades or building new specify harmonic cancelling transformers.
4. Be sure that your power loads are evenly distributed across all power phases.
5. Be sure that all power connections to plugs and outlets are properly wired and verify correct power outlet voltage with a voltmeter at various locations throughout your facility or building.
6. Whenever possible specify copper wiring. Copper runs cooler and saves energy.
7. Install transient voltage surge suppression (TVSS) devices at the main electrical service panel to protect from voltage surges. Install TVSS devices at computer equipment level.
8. Ensure proper installation of grounding electrode by using metal water main, building steel, concrete encased electrodes (Ufer ground) and deep driven ground rod.
9. Inspect for and remove any neutral to ground bonding jumpers in any sub-panels downstream of the main electrical service panel and main bonding jumper. 
10. Install wire conductors one size larger than is required by the National Electrical Code (NEC) to increase energy efficiency.
11. Do not use the conduit as the equipment ground. Be sure to install an equipment ground wire conductor for each computer and electronic branch circuit.
12. Safety first. Train yourself and your staff on all the safety requirements when working in and around electrical equipment. Leave the work to the professionals.

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