Good day and warm Greetings From Zubair!!! We all hope that everything is well! This is to introduce to you our company, Al Zubair General Trading Est. Kindly see below company profile for your reference! Our company (Electrical Division) is Oman based who has its business in diversified activities spread over Oman, United Arab Emirates, Saudi Arabia, Qatar & Nigeria. Establishing our presence here in UAE from 1989, we have been fortunate to associate with major electrical brands like ABB, Hager, L&T, Eaton in LV Switchgear apart from other major cables and lighting products. Being one of the authorized distributors for ABB, our product basket covers complete range of Power, Control and Automation products. Apart from component supplies, we are also “Authorized Value Provider” for
Identify Untagged 6-Leads out 3~ Motor
Part of being in Maintenance or Engineering Department in plant is the Corrective Actions where equipment or parameters are having issues or fault. To be an expert in solving problems or troubleshooting requires years of experience in plant. One of the hardest parts of corrective maintenance is dealing with aged systems. “Abandoned” electrical panels, system with obsolete models, etc. Untagged 6-phase motor could be one of them. In case of emergency that we need to use a motor with untagged leads, what would you do? This article will show you how to identify untagged 6-leads out, 3-phase motor. This is one of the topics that I thought to my class when I worked as a part-time teacher. Before you do the steps, make
Redundant Systems that I have encountered
Reliability is one of the most important aspects we should be focused on especially when it comes to Plant Maintenance. Frequent shutdowns in plant could be caused by poor maintenance management and lack of advance tools to keep the system running. For a plant working 24/7, most of the running equipments should be treated critically and monitored regularly. However, Redundant Systems are used to save the plant from shutdowns if failure occurs. Aside from back-up power we should always thought of back-up systems that will manually or automatically take over the operations in the event of fault or alarm. In this article, I will share with you the redundant systems that I have encountered by working in Maintenance Department and Engineering Design.
Maintenance and Reliability in Plant
As a technician in plant, I learned that Maintenance and Reliability are the two things we should focus on. In most cases, plant personnels are more focused on Corrective actions rather than Preventive and Predictive approach. In this article, I'm going to share with some of the things I've learned from my previous job in plant. However, we will focus more on Vibration, Lubrication, Energy and Intercoolers. Table of contents 1. Types of Maintenance2. Vibration analysis3. Oil analysis4. Monitoring of the coolers5. Energy consumption Types of Maintenance The various analyses are made at frequencies determined by the strategy of maintenance which has been chosen. It is thus appropriate, for that, to define the main types of maintenance met: Preventive Maintenance Stops are envisaged systematically, at
Measurements (CT, PT, and Tore)
This article will discuss about the three common Electrical Measurements we can found in Switchgears and Panel boards. I learned this electrical measurements when I worked with a gas manufacturing plant as a Cadet Engineer. However, this is just few of the measurement devices that we have in the field of Electricity. This article will focus on Current Transformer, Potential Transformer and Tore that are used as metering device. Table of contents 1. Current Transformer 2. Potential or Voltage Transformer 3. Tore or Residual Current Sensor Current Transformer The current transformer makes it possible to reduce a high intensity current to a value of 1A or 5A exploitable by the measurement apparatus and the protection relays. (1A and 5A being standardised values). It includes a primary
Design Guide for PLC Panel
In a modern world of engineering, one of the successful innovations ever made is the Programmable Logic Controller or the so called PLC. PLC with Redundant CPU and separate racks for Input/Output Modules In this article, I'm going to share with you how I do the designs for PLC Control Panels based on the previous projects that I have handled. Table of contents 1. Definition of terms2. Essential tools3. Review of project specifications4. Enclosure type5. Panel cover devices6. Internal components7. Auxiliary items Definition of terms What is PLC? Programmable Logic Controller or PLC is a combined hardware and software tool. It function as the brain of the automated system. It monitors feedbacks and input signals by means of Input Modules. Also, it regulates the commands and output
Lightning Protection
Formation of lightining The ground and the electrosphere, the conductive zone of the atmosphere (thickness in the order of 50 to 100 km), constitute a natural spherical condenser which charges by ionization, leading to an electric field directed towards the ground in the order of a few hundreds of volts/meter. The building up of the stormy clouds, masses of water in the form of aerosols, comes with the electrostatic phenomena of charges separation: the light positively charged particles are pulled by the ascending airstreams, and the heavy negatively charged particles fall because of their weight. It also happens that small islands of positive charges are located at the base of the cloud, at the place of intense rains. All in all,
Top PLC Interview Questions
Thinking about your next job interview? Here are the Top PLC Interview Questions to fully guide you and increase the chance on getting the job you desire. 1. What is PLC? PLC stands for Programmable Logic Controllers, PLC is an industrial computer used to monitor inputs signals or feedbacks and to regulate (turn on / off) their outputs or commands to automate a device or process, depending on their state making choices based on their program or logic. PLC is a software and hardware combined. It functions as the machine’s brain or system for control mechanisms for automation. 2. What is the role of PLC in automation? PLC Senses input via I/P modules, processes logic via CPU and memory, and provides output via output module. PLC plays most important role
Machine Protection
Introduction Overheating of a motor due to an abnormal use shortens considerably the life time of its components and causes short-cuts. Overloads are tolerated only for a limited period of time. Concerning short-cuts, their effects are destructive and they must be quickly cut off. Fault types Internal Faults That type of internal faults generally appears when insulating components areageing. It is then preferable to release the protection as fast as possible. Those faults can be detected by comparing the ongoing and outgoing currents of the same phase. The protection is then provided by an percentage differential overcurrent relay connected to two sets of three current transformers placed on each input and output phases of the stator. Because of the imprecision linked to the TC, the fault current
Transformer Science
20/25 MVA Oil-filled Transformer Transformer is an electrical static machine whose aim is to increase and decrease an Alternative Voltage. Runs on magnetic affect, without any part being in motion. Usefulness of Transformers The transport of electrical energy at high voltage allows to convey less current in the lines (P = 3 V I cos ). For given amount of losses, transportation under limited current, allows to use conductors with lower cross sectional areas, i.e. cheaper! Also structures that can stand these conductors will be less restrictive because a lower cross sectional area also means a reduced weight. That is why it is cheaper to transform the voltage and use intermediate voltages, especially when distances become longer… The transformer also provides a galvanic insulation, i.e.. the primary and