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Distribution networks are susceptible to spurious transients, both low and high frequency ringing, conducted and radiated emissions resulting from arc flash events. This paper introduces the phenomena of resonance and electromagnetic radiation emissions associated with the conductors and inherent capacitance. The paper addresses the effect on the peripheral equipment used for control and protection...
There are a number of competing online partial discharge (PD) measurement systems available in the marketplace today. Since most of these systems utilize procedures and equipment that differ from one another, it has been difficult to compare the results between the varying systems and difficult to provide guidelines that apply to all. To undertake a comparison of several competing systems it was necessary...
This paper describes the design, testing, and commissioning of modified low voltage switchgear located in a major chemical and refining complex. The intent of the redesign was to significantly reduce the incident energy at the line and bus side of the low voltage lineups. The company mandated that the incident energy should be reduced to Category 3 (25 cal/cm2 or less) at the low voltage line side...
This paper reviews the current legislation for certifying rooms in hazardous areas with the following aims: to describe the major aspects of certifying rooms for use in the international market place and establish the appropriate body for this assessment. This is achieved by reviewing the current status of the International Electrical Commission, its member states and the progress made towards being...
The petrochemical industry has increasing interest in condition monitoring of stator winding insulation during service. Factory acceptance specifications developed from the American Petroleum Institute (API) standards often require a PD and/or power factor tip-up (PFTU) test for brand new windings as a factory acceptance test before installation machine is installed. Petrochemical industry users often...
The petroleum and chemical industries are facing pressure to become more energy efficient and sustainable. The use of green energy is a feasible option to address that issue. This paper discusses the application of various source technologies available to offshore petroleum and gas production platforms. The pros and cons of each source is considered, as applied to critical systems, including safety...
The electrical distribution systems in industrial facilities often incorporate a secondary-selective design where loads are fed from redundant transformers normally loaded to less than 50% of their kVA rating. When transformers are operating in ambient temperatures above 30 °C, IEEE Std C57.91 provides guidelines on how to load the transformers to compensate for the accelerated insulation aging. This...
There has been significant progress on arc-flash research in recent years, but there has been little focus on how the internal configuration of equipment affects the incident energy released. The relationship between low voltage motor control center (MCC) unit configurations and incident energy exposure resulting from an arc flash is examined in this study. Testing was conducted using actual MCC structures...
Shipboard control systems equip an expert operator with the ability to safely open and close breakers to facilitate electric plant operations. In more advanced systems, ship integrated power systems are equipped with automatic control systems that provide power management by automatically connecting and disconnecting power generation sources based on plant's present load and on-line generation capacity...
Every industrial plant has an electric distribution system. Depending on the size of the power distribution system, layout of the plant, power source and operation, the power management may be more or less complex. This paper describes an installed and operating PLC based Power Management System (PMS) for a mid to large size industrial plant. The aim of the PMS is to avoid a collapse of the electric...
Thermal issues shorten motor life. Modern motor relays must protect for these effects, which can occur for motors from small to large (50 HP and greater), and for all voltage operational levels. However, being too conservative on thermal limits decreases motor productivity. An ANSI/IEEE 49 thermal element creates a realistic thermal model of the motor because the element takes the load level and negative-sequence...
This paper presents different aspects of using temperature sensors as a part of the motor thermal model. Different types of sensors, mostly used on medium voltage machines, are presented. The most common solutions of building sensors into motor windings are described. The differences between induction and synchronous motors are discussed regarding the benefits of temperature sensor usage. It is considered...
Induction motors are widely used as the workhorses for the petroleum and chemical industry. As such, their efficiency is an important issue for both the users and manufacturers. As currently designated by IEC (International Electrotechnical Commission) [1], the efficiency of induction motors is classified by four levels: standard (IE1), high (IE2), premium (IE3), and super premium (IE4) efficiency...
IEEE Std. 80 “IEEE Guide for Safety in AC Substation Grounding” is most commonly used in the design of substation ground grids and is the basis for today's commercially available software. This paper discusses alternate design approach for substation grounding in areas that have high soil resistivity. It discusses various methods for designing a substation grounding system without changing the characteristics...
The Proposed “IEEE 45.8 Recommended Practice for Electrical Installations on Shipboard - Cable Systems” will reference EHT (Electrical Heat Trace) for heating pipes, tanks, and instrumentation on-board ocean-going vessels. The globally recognized IEEE 515 Standard for resistance heat tracing addresses “traditional” freeze protection and temperature maintenance applications on-board tankers and FPSO...
Arc Flash (AF) protection is very important for all power and process industries to maintain safety of personnel at the workplace. As the amount of incident arc flash energy is a function of time, every millisecond counts in the race towards reducing the amount of incident energy to which an individual might be subjected. Since the introduction of the first arc flash detection technology, the ability...
Since its initial publication in 1983, IEEE 515 has been the primary industrial trace heating standard in the US and the basis for many other countries and international industrial trace heating standards. With the overall objective of one worldwide standard for industry, the goals of revised IEEE P515 were to incorporate technical updates and further harmonize with international industrial trace...
Electric submersible pumps (ESP) are used in a wide-range of applications from onshore to complex offshore, deep water, or subsea applications. Premature failures are undesired as they result in repair or replacement costs, but worse - downtime. This paper presents the challenges faced by the authors at an onshore oil field. The site experienced several ESP failures after drilling and operating 10%...
A number of different motor configurations have been proposed to either replace or augment the commonly applied three phase induction motor. Motors with permanent magnets, segmented stators, concentrated windings, five or six phase windings, cast copper rotors, salient pole rotors, solid rotors, and hybrid combinations of these have all been touted as having superior characteristics in one way or...
For more than 50 years research has shown that a correlation exists between the number of incidents, injuries, and fatalities. Investigation into electrical incidents indicates there is more to understand about the causal effect of the number of incidents occurring. Many electrical incidents are caused by undesirable actions of people. These are called unsafe acts. Why do people perform unsafe acts?...
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