Relay Panels Research Articles

A Method for Monitoring Operation Status of Oil-immersed Transformer Based on the Baffle Angle Characteristic of Gas Relay

A gas relay in the transformer, an important non-electricity protection equipment, only triggers the stem leaf spring for the serious gas alarm when the baffle rotates to a certain angle, which cannot judge the transformer fault in the event of heavy gas before running state and fault development process, this paper puts forward a kind of based on gas relay panel corner of transformer running state monitoring methods. The partial structure of the gas relay is improved, and the baffle corner signal is extracted by installing a Hall sensor on the back of the baffle. On this basis, this paper develops a test stand capable of simulating the baffle characteristics of gas relays at different fault energies. Subsequently, the baffle angle variation law under different fault energies is studied, and the influence of pipe pressure and pipe flow rate on the baffle angle is given. The results show that, based on this improved gas relay, the real-time baffle angle information can reflect the internal operating state of the transformer and provide an effective method for transformer operating condition monitoring.

Optimization of Condensate Transfer Pump in the Hydrocarbon Condensate Stabilization Unit of Natural Gas Liquefaction Plant – An Industrial Case

PT. Badak NGL is a commercial LNG producer located in Bontang, Indonesia. In recent years, the decline in LNG production of PT. Badak NGL results in a lower hydrocarbon condensate flow rate. To prevent power losses since its pump operated at below rating, a new operation scheme was proposed. This new scheme adjusts the way of pump is operated without any alteration in terms of pump characteristics. Three pumps operated intermittently for 8 hours per day at a maximum flow rate. The pump power consumption was calculated based on electric current data monitored relay panel. The results show that the pump energy saved by 60% with the absolute value of annual energy efficiency of 957.7 MWh. This study contributes to reducing the greenhouse effect by 412 tons eq CO and the annual production cost of around USD 130,000. The new scheme reliability examines by evaluating pump vibration, pump performance, hydrocarbon condensate quality, and condensate tank liquid level. The result shows that the pump’s vibration in the range of 0.21 in/sec with a steady winding temperature.

Substation Indoor Wheeled Robot Inspection Visual Blind Pressure Plate Recognition

In order to solve the problem of wheeled robots in the main control room of the substation due to the height of the robot and the shooting distance, the main camera cannot take a complete picture of the bottom pressure plate of the relay protection pressure plate cabinet during the inspection process and perform open/close state and label image recognition. Propose install a wide-angle secondary camera on the side of wheeled robot, and targeted proposal for the correction of distorted images taken with a wide-angle lens using a division model, improving the accuracy of decompression plate checks. Experiments have shown that, the proposed approach is practical and feasible, effective solution for indoor wheeled robot relay panel cabinet inspection visual blind spot shooting problem, enhanced the effectiveness of wheeled robotic inspections in the main control room of the substation, improved platen verification accuracy.

Conveyor belt experiment setup for programmable logic controller education

Programmable logic controllers (PLC) have been one of the most widely used controllers in industry. They have a graphical programming language interface resambling the relay panels which they are intended to replace so that the transition from relay panels might be swift and smooth. Although learning this programming language is easy, real life experiments are essential for students to gain greater understanding of the logic behind the language. However, it is generally too expensive to provide an experimental set-up for students to test their theoretical knowledge. For this reason, a conveyor and feeder system was developed as a low cost 3D printable design using a CAD program and implemented for use in a control laboratory. Using this conveyor set-up, students can experience how to program a practical example of a PLC devices used in industry together with an introduction to actuators and sensors. Reading actual sensors and using actuators via the inputs and outputs of a PLC to control a real life system will be far more effective than simulator alternatives.

The Job Analysis of Electrical Maintenance Workers And Training Needs Analysis based on DACUM Approach

본 연구의 목적은 H사에 재직 중인 생산에 직ㆍ간접적으로 관여하고 있는 전기정비직 종사자를 대상으로 직무를 분석하여 책무와 작업을 도출하고, 작업을 수행하기 위해 필요한 지식/기술/태도/도구를 도출하며, 설문조사를 통한 교육요구분석에서 우선순위를 파악하는 것이다. 연구문제 해결을 위하여 DACUM 직무분석을 통해 직무를 규명하고 4개의 책무와 33개의 작업을 도출하여, 설문조사를 실시하였다. 이후, 작업에 대한 검증을 진행하였고 교육요구분석을 수행하였다. 연구는 H사 전기정비직 종사자를 대상으로 실시하였으며, DACUM 직무분석을 위한 위원회에는 퍼실리테이터 1명과 코디네이터 1명, 전기정비직에 종사하는 최소 19년 이상의 경력을 가진 내용전문가 7명이 참여하였다. 이후 DACUM 직무분석을 통해 도출된 결과를 검증하기 위해 현업부서 관리직 전문가 5명이 참여하였다. 설문조사는 전기정비직에 종사하는 전체 342명을 대상으로 실시하였으며, 총 342부중 256부를 회수하였으나 최종분석에는 222부가 활용되었다. 연구결과 첫째, 전기정비직 종사자의 직무는 ‘수배전 유지보수’, ‘자동제어 유지 보수’, ‘전기기기 유지보수’, ‘계측 장비활용 유지보수’ 의 4개 책무와 33개의 작업으로 구성되어 있음을 확인하였다. 둘째, 도출된 33개의 작업을 수행하기 위해 필요한 지식/기술/태도/도구를 도출하였다. 셋째, 설문결과 전기정비직 종사자 작업의 우선순위를 규명하기 위하여 t 검정과 Borich 요구도 공식을 통한 우선순위 분석, The Locus for Focus 모델을 활용한 요구도의 상위 수준을 결정하였다. Borich 요구도와 The Locus for Focus 모델을 활용한 최우선 순위의 작업은 총 8개로 ‘고압판넬 차단기 유지보수하기’, ‘고압판넬 계전기 유지보수하기’, ‘고압판넬 계기류 유지보수하기’, ‘plc H/W 유지보수하기’, ‘plc S/W 유지보수하기’, ‘plc network 유지보수하기’, ‘드라이브 H/W 유지보수하기’, ‘드라이브 S/W 유지보수하기’로 확인되었다. 본 연구를 통해 전기정비직 종사자의 DACUM 직무분석과 요구분석 결과 교육적 요구가 확인되었다. 이를 바탕으로 직무교육과정 설계시 효율적이고 성과 있는 교육과정을 개발해야 한다. 다양한 전기관련 업무를 취급하고, 생산에 직ㆍ간접적으로 관여하는 전기정비를 담당하는 종사자들에 대한 인력양성의 중요성을 다시 한 번 일깨우는 계기를 제공함과 동시에 그들에 대해 전략적이고, 체계적으로 육성하기 위한 계획수립과 운영, 평가 측면에서 본 연구결과가 중요한 자료로 활용될 수 있을 것으로 기대한다.The purpose of this study was to figure out the recognition difference about the level of importance(priority) of task of electrical maintenance workers that are directly or indirectly involved in the production of H company. The way to continue the study, analyze the position, and gather information about the duties and tasks for the position. After that, find out required knowledge, skill, attitude, and tools to perform the task. And then, make a priority from the training needs analysis through a survey. To implement the project, investigate duties through the DACUM job analysis and find out 4 of their duties, 33 tasks and conducted a survey. After that, we went through the verification of task and training needs analysis. The subjects were electrical maintenance workers at H company, and the committee for DACUM job analysis consisted of a facilitator, coordinator and 7 professionals of the field with over 19 years of experience each. Also, 5 work site management staff experts participated in the verification process of the result afterwards. The survey consisted of 342 electrical maintenance workers. Only 256 out of 342 participated in the survey. However, only 222 of those were used in final analysis. The first result of this study confirmed that the 4 duties were ‘power receiving and distribution maintenance’, ‘automatic control maintenance’, ‘electric device maintenance’, and ‘measuring device maintenance’ and 33 tasks that are most important to an electrical maintenance worker’s duty. Second, deducted knowledge, skill, attitude, and tools that are required to perform the 33 tasks. Third, to detect the priorities of the tasks of electrical maintenance workers, analyze priority based on the examination, Borich Needs Assessment Model and used The Locus for Focus Model to make a decision of superordinate standard. It confirmed that the top priority has 8 tasks based on Borich Needs Assessment Model and The Locus for Focus Model and they are ‘high voltage circuit breaker panel maintenance’, ‘high voltage relay panel maintenance’, ‘high voltage instruments panel maintenance , ‘plc H/W maintenance’, ‘plc S/W maintenance’, ‘plc network maintenance’, ‘drives H/W maintenance’, ‘drives S/W maintenance’. The training needs was confirmed through the DACUM job analysis and needs analysis of the study results for the electrical maintenance workers. Based on this study, it should develop a productive curriculum when we plan the competency curriculum. In conclusion, this study provided the opportunity of the importance of human resource training for electrical maintenance workers that handle a variety of electrical works that are directly or indirectly involved in the productions. Also, the results of these studies are expected to be utilized as a useful reference for planning and management, and evaluation for strategic and systematic development of electrical maintenance workers.

Up-gradation of Conventional Control Panel with PLC for the Total Utilization of Machine

In the beginning of industrial revolution, especially in 1960 to 1970, automated machines wear controlled by electromechanical relays. These relays wear hardwired together inside the control panel. Many of the times the control panel was so huge that it would cover entire wall. Every connection in the relay logic must be connected. Wiring is not always perfect; it takes time to troubleshoot the system. This is very time consuming Process. On top of that the relays have limited contacts. If modification is required, the machine has to be stopped, the space may not be available and wiring has to be traced again to accommodate changes. The control panel can only be used for the particular process. It cannot be changed immediately to a new system. It has to be redone. In terms of maintenance, an electrician must be well trained and skilful in troubleshooting the control system. In short, the conventional relay control panel is very inflexible.

Intelligent Lighting: Meeting Your Project's Sustainable Goals

ABSTRACT A definition of “intelligent lighting” is: Intelligent lighting is a lighting system that utilizes bi-directional communication between control and luminaire, with the intelligence residing in each uniquely addressed ballast. As a result of the intelligence residing in the ballast, control communication is independent of the power circuits, eliminating the need for dimming and/or relay panels and the home runs from the load to these panels. Essential “intelligent” characteristics of a DALI installation are: •The individual addressable control and monitoring of lighting systems.•Precise and repeatable digital dimming.•Design fl exibility and ease of installation.•OPC server for BMS clients.

FROM ELECTRIC MOTORS TO FLEXIBLE MANUFACTURING: CONTROL TECHNOLOGY DRIVES INDUSTRIAL AUTOMATION

Industrial Automation has evolved from stand-alone, hard-wired relay panels to a contemporary, networked system that supports flexible manufacturing and enterprise integration. From precision control of machines and robots on the factory floor to flexible coordination of multiple cells of automation, advancements in control technologies have driven the evolution of industrial automation. The confluence of five technologies, control, computing, communications, software, and materials, is shaping the future direction of industrial automation systems. This paper summarizes the major technical trends, and highlights the continuing opportunities and challenges for the application of control technologies in industrial automation.

Programmable logic controllers versus personal computers for process control

It is proposed that Personal Computers (PCs) can be used effectively for the same industrial applications as Programmable Logic Controllers (PLCs). The basic concepts related to the operation of a PLC to emulate the behavior of a relay panel are explained. This is used to build a simple model for using standard PCs in the same applications as PLCs. This is demonstrated using a simple example of an automated process. Sample code in a standard high level language is presented that can be used as a template for future developments. Finally, the potential advantages and enhancements that can result in using PCs for process control are presented.

Principal Details of Design Drafting for Substations by Computer

The Bonneville Power Administration has been developing a system for producing substation design drawings by using automatic data processing methods. Although the system is not yet 100-percent operational on all phases of substation design, it is operational on 115-kV one-line diagrams, buslayouts for 500-kV breaker- and-a-half and ring-bus schemes, 115-kV customer's service stations, and some switchboard and relay panels. The basic programming structure has been established, and the system offers a practical and economical method of decreasing the man-hour requirements for substation design, where repetitive-type drawingsmust be produced for construction purposes. The project has been separated into six basic parts: 1) developing the basic logical structure, 2) reducing the graphical components to numerical data, 3) retrieving and assembling the necessary components for a specific drawing, 4) transforming the numerical data back into graphic form ( plotting), 5) generating a bill of material, 6) writing a material summary list. Ways of applying these parts to design drafting are discussed.

Training the Mentally Retarded in the Production of a Complex Product: A Demonstration of Work Potential

Mildly and moderately retarded residents of a state institution for the mentally retarded were trained to assemble relay panels and similar psychological apparatus in a sheltered workshop. The function of the shop, training techniques, and some problems encountered, are discussed.

Application of Experimental Vibration Data to the Design of Viscoelastic-Damped Structures

Various theoretical analyses of idealized structural elements embodying a viscoelastic shear-damping mechanism are available in the technical literature. The damping properties of viscoelastic-damped beams, plates, and simple structural junctions have been investigated with simplifying assumptions made with regard to the uniformity of structural-member cross section, the type of mass-loading distribution, and the nature of physical constraints and boundary conditions. Actual structural fabrications associated with electronic and electromechanical equipment require appropriate consideration of concentrated mass loadings, boundary conditions, fastening devices, strength requirements, and environmental conditions. This paper discusses the application of experimental vibration data to the design of viscoelastic-damped structures and presents a number of examples in which viscoelastic shear-damping materials have been employed in the fabrication of structures for modern electronic and electromechanical equipment. Experimental data are presented for a laboratory electronic-chassis model, an antenna gearplate, an aircraft equipment-mounting rack, a gyroscope-mounting system, a missile flap-actuator relay panel, two missile-arming and -fusing structures, and a satellite decoder-receiver electronic equipment. In most cases, the structural-damping property of the system is measured before and after the application of a viscoelastic damping treatment in order to indicate the degree of vibration control that has been provided.

Traffic Control by Light Beams For Major-Minor Intersections

The object of this traffic controller is to keep the signal green on the major street, and to give the green signal to the minor street only when requested. The minor street vehicle can always get the green signal after a short wait, while the major street receives green light for as much extra time as the minor street traffic permits. Two experimental horizontal beam installations, which accomplish the above object, are now in operation in Wilkinsburg, Pennsylvania. The focussed light beam, phototube unit, relay panels, and associated circuits are described in this paper.