Title: Power
Course: 2016FA-MCO-110-401 > Section: Module 3: Power

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Power

Power is a key resource in critical facilities and often a continuous supply of power is required to continue operating. Advanced planning is required in order to guarantee this uninterrupted stable power supply.

A facility’s required uptime will be one of the primary considerations when planning for power. Other common considerations will include estimated consumption, estimated future consumption (room for growth), and availability of power from utility sources.

Power Quality

Spikes or surges in power and brownouts (dips in power) can be damaging to electronics and other equipment. The required uptime of a mission critical facility translates into lost revenue and damage to reputation if power loss causes downtime. Therefore a reliable and stable source or sources of power are a priority. In addition to providing a stable power supply, many critical applications also require power that is free from most electrical noise. This power is sometimes referred to as clean power and the target waveform of its voltage is as close as possible to a sine wave. The phrase good power quality is sometimes used to describe highly available, noise-free (sinusoidal wave form), and within frequency and voltage tolerances [1]. Good power quality is important in most mission critical applications.

Three Phase versus Single Phase

Both single phase and three phase devices can be powered by a three phase power supply. Most of the AC power that is generated is three phase power. Three phase power is more efficient than single phase power since more power can be supplied within the same period of time [2]. It contains three single phase sine waves that are placed 120 degrees apart and provide near-constant power [3]. A single phase wiring system however provides an almost on/off effect because of the up and down of the single sine wave [3].

Load Balancing

Load balancing is the process of evenly distributing current and voltage. If a load is unsymmetrical, it can cause the system to become unbalanced.

In three phase systems, when each phase has an equal amount of current it can be said to be balanced.

“As the load comes closer to perfect balance, the current draw is more evenly distributed among the three-phase lines (more headroom), and total current flowing in the three lines is minimized” [4, p. 550].

Objectives met:
- C3
- 3.1