EEP - Electrical Engineering Portal

The capability of reading different types of drawings is an essential skill to perform almost all of the engineering tasks. The engineering drawings form the building blocks of industry method to convey detailed information to implement, gather, troubleshoot, maintain, and run a system. Basically, the very first step to learning how to read such drawings is to become acquainted with standard procedures and basic symbols that are utilized in these drawings. The information contained outside the drawing areas in a print is essential to comprehend the given information in the drawing areas. The title block, revision block, grid system, notes, and legend are all examples of the non-drawing areas in the print. Usually, the terms print, diagram, and drawing are used interchangeably to indicate the full drawing package. https://lnkd.in/eQTUtEW

The most critical characteristics of a circuit breaker are the opening and closing velocity values, along with the stroke or travel distance. They are generally dictated by the requirements imposed by contacts. The opening and closing velocities are crucial for the contacts to prevent contact erosion and contact welding. The circuit breaker stroke is fundamentally associated with the circuit breaker’s capacity to withstand the required operating dielectric thermal stresses, which has a direct relationship to the total contact gap and the rate of its expansion. The operational characteristics must be defined for each mechanism in conjunction with the circuit breaker in accordance with IEC62271-100. https://lnkd.in/dwza-skq

Selectivity study of a power system is usually considered as an advanced job for advanced engineers, mostly relay protection engineers. This article will try to get close to a few important selectivity principles in a simple manner. It’s important to fully understand that protective devices form a logical system in relation to the power system structure and its earthing system. Protective devices are the brain of a power system based on the principle of selectivity that consists of isolating the part of the network affected by the fault, and only that part, as quickly as possible, while all the other unaffected parts of the network remain energized. There are various ways of ensuring proper selectivity in electrical network protection: https://lnkd.in/e4bSdxf

The polarity indications for transformers are well established by standards that apply to all types of transformers. There are two varieties of polarity: subtractive and additive. Both follow the same rules. Power and instrument transformers are subtractive, whereas some distribution transformers are additive. The polarity marking can be a dot, a square, or an X, or it can be indicated by the standardized transformer terminal markings, the practices varying over the years. Polarity is designated by an X in this technical article. Read more https://lnkd.in/dyha2gwW

This “Study Guide” is designed to provide the electrical troubleshooter with a review of, and the mechanical troubleshooter with an introduction of, basic electrical skills needed for him/her to safely and more efficiently carry out their duties in the plant environment. After successful completion, the troubleshooter can improve their understanding of DC, AC, three phase circuits, Relays, Contactors, PLC, Electronics, and other related technology. https://lnkd.in/eNZe8Cu

According to the breaker internal wiring in Figure 7b, LS4 is NC when the breaker is in the test position. Then, the breaker is closed from the SW2 in emergency mode. The circuit enclosed in the dashed-line box will be elaborated later. The BCPU signals the closing command in case of a local SW1 position, whereas SAS or SCADA commands the BCPU to close the breaker for the remote position. Under these two statuses, there are additional contacts and interlocks along the way. A limit switch (LS6) residing the dashed-line-dotted box, which represents the breaker position in service mode (i.e. LS6 is closed if the breaker is in service position). The remaining contacts along this circuit are related to the panel relays being reset after a fault clearance, busbar relay reset, and breaker failure contacts. The breaker must not be closed unless a fault is cleared and relays are reset (normally lockout relay (86)), which are taken care of in these three concatenated contacts in this circuit. Note that the capacitor feeder example has two relays for redundancy purposes, but if a panel has one relay, then there would be only one-panel relay in the interlock. https://lnkd.in/eYnupRe

There are many factors that influence final specification of a transformer. However, the following ten factors MUST be considered when specifying transformers. https://lnkd.in/erMVa92

A voltage transformer selection scheme ensures that the correct secondary voltage is routed to the relevant devices, especially in substations with complex configurations like double busbar systems. Synchronization, a critical operation, relies on VTs to provide voltage signals from both the line and busbar sides of a circuit breaker. This process ensures that two electrical systems can be safely connected by matching their voltages, frequencies, and phase angles. Without a VT selection scheme, substations would require additional VTs, increasing. By dynamically selecting the necessary voltage signals, these schemes optimize equipment usage, reduce expenses, and maintain operational efficiency. Read more https://lnkd.in/dtbBHuBv

Most projects suffer due to lack of capability of the project proponent and an inept mindset among its engineers and designers that extensive inclusion of environmental mitigation measures in the project design leads to very high construction and O&M costs in the long-run. At the planning stage itself, land availability is one of the main factors that govern the establishment of a substation project. This involves a contiguous piece of land that can infringe upon scarce populated/forest/cultivated land. While identifying the power substation as part of the system for a generation project or as a part of distribution grid, preliminary site selection is done by the utility based on the shortest length of the incoming (incomer) and outgoing lines which are normally surveyed/marked on the 1:50,000 maps/topographical maps of the area with details about proximity to sensitive receptors in the area. https://lnkd.in/dYMG4hZr

With hopes that this technical article will help clear up some of the confusion around substation physical security and provide some answers to some of the most frequently asked issues. Its purpose is to serve as a starting point for creating and implementing a physical security program, rather than to address every possible concern or offer final conclusions. A methodical approach can be used to create and implement a security measures. In this article, we’ll go over the fundamentals which will help you figure out what kind of physical security measures are best for your electric system. Be advised that the subject matter of this article is limited to physical substation security, more especially to safeguards put in place to avoid unauthorized access. https://lnkd.in/dUMDJvzc