The word audit is derived from a Latin word "audire" which means "to hear". During the medieval times when manual book-keeping was prevalent, auditors in Britain used to hear the accounts read out for them and checked that the organisation's personnel were not negligent or fraudulent. Quality Audit
Quality audits are performed to verify conformance to standards through review of objective evidence. A system of quality audits may verify the effectiveness of a quality management system. Quality audits are essential to verify the existence of objective evidence showing conformance to required processes, to assess how successfully processes have been implemented, …show more content…
There are economic impacts on utilities, their customers, and suppliers of load equipment. The quality of power can have a direct economic impact on many industrial consumers. This usually means electronically controlled, energy-efficient equipment that is often much more sensitive to deviations in the supply voltage than were its electromechanical predecessors. Industrial customers are now more money associated with these disturbances Besides the obvious financial impacts on both utilities and industrial customers, there are numerous indirect and intangible costs associated with power quality problems. Residential customers typically do not suffer direct financial loss or the inability to earn income as a result of most power quality problems, but they can be a potent force when they perceive that the utility is providing poor service. Home computer usage has increased considerably in the last few years and more transactions are being done over the Internet. Users become more sensitive to interruptions when they are reliant on this technology. Load equipment suppliers generally find themselves in a very competitive market with most customers buying on lowest cost. Thus, there is a general disincentive to add features to the equipment to withstand common disturbances unless the customer specifies otherwise. Many manufacturers are also unaware of the types of disturbances that can occur on power …show more content…
For example, = 5 refers to the fifth harmonic component with a frequency equal to five times the fundamental frequency. If the fundamental frequency is 60 Hz, then the fifth harmonic frequency is 5×60, or 300 Hz. The harmonic number 6 is a component with a Frequency of 360 Hz. Dealing with harmonic numbers and not with harmonic frequencies is done for two reasons. The fundamental frequency varies among individual countries and applications. The fundamental frequency in the U.S. is 60 Hz, whereas in Europe and many Asian countries it is 50 Hz. Also, some applications use frequencies other than 50 or 60