1. Do not use the conduit as the equipment ground. Install a equipment ground wire conductor in each computer and electronic branch circuit. This provides for a true ground path return for electronic equipment thereby eliminating mechanical conduit connections as the only ground path. The Institute of Electrical and Electronics Engineers (IEEE) recommends this continuous ground conductor for computer and electronic equipment. 

  2. Each computer connection or electronic branch circuit should have individual phase, neutral, and ground conductors. The use of shared neutral conductors as with multi-wire branch circuits is not recommended.

  3. Install transient voltage surge suppression (TVSS) devices at the main electrical service panel to protect from voltage surges.

  4. Install individual TVSS devices at each computer system or at any other  sensitive electronic equipment load. This is inexpensive protection for power problems generated within the building electrical distribution system. Don’t forget to protect copiers, printers, and fax machines.

  5. Connect laser printers and heavy duty copiers on individual 20 Amp branch circuits. Laser printers and heavy duty copiers produce high current surges which cause an increase in the neutral to ground voltage. This action can potentially damage other computer and electronic equipment if they are on the same branch circuit.

  6. Ensure proper installation of grounding electrode by using metal water main, building steel, concrete encased electrodes (Ufer ground) and deep driven ground rod. This can be accomplished by the installation of a main ground bar (MGB).

  7. Specify harmonic canceling transformers in the design of HIGH-TECH facilities. Switch-mode power supplies and  non-linear loads such as personal computers, UPS systems, adjustable speed and variable frequency drives, and electronic lighting ballasts generate power harmonics.  Harmonic canceling transformers will treat the harmonics thereby removing them from the electrical system.

  8. 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.  

  9. Evenly distribute power loads across all power phases. This will help to stabilize voltage and increase power efficiency.

  10. Install wire conductors one size larger than is required by the National Electrical Code (NEC) to increase energy efficiency. By increasing the wire size,  reduced power losses offset the cost of the wire and produce savings on energy costs. For most new construction projects the cost of labor and conduit for the installation outweigh the cost of the wire. The increased size of the wire can pay for itself in less than two years. At the same time, increased wire size is insurance against future changing needs and assures lower voltage drops. Copper upsizing also minimizes costly operations problems, particularly downtime due to overheated or failed equipment. Reliability and service life of electrical equipment are substantially increased.

  11. Install electrical equipment that contains more copper. Copper runs cooler and saves energy and money. The more copper your electrical equipment windings and cabling contain the less costly energy you’ll lose as heat because copper is the most efficient conductor available. The law of physics says that all electrical equipment wastes energy in the form of heat. It's expressed as: IČR, where I=current and R=resistance. Sit down with your plant engineer or facilities manager. Compare the costs and compare the savings. You will find that energy efficient electrical equipment and cabling put the IČR law on your side.

  12. Check your outlet wiring. Many power outlets are improperly wired. The most common problem is reverse polarity where the hot and neutral wires are reversed. The second most common problem is an open ground or none existing ground wire connection.

  13. Verify correct power outlet voltage with a voltmeter at various locations throughout your facility or building. The 120 volts outlets should be 120 volts ± 5%. Also check the neutral to ground voltage. Anything over 2.0 VRMS indicates excessive voltage drop, high harmonics, or poor grounding.


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