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[ { "title": "LEARN | Condition Monitoring (part 4)", "nid": "496", "body": "\u003Cp\u003E\u003Ca href=\u0022https://www.magnetgroup.co.za/solutions-electrical/index.php\u0022\u003E\u003Cimg alt=\u0022motors\u0022 data-entity-type=\u0022file\u0022 data-entity-uuid=\u00224253c9e9-a97c-401a-9694-51f01c772adc\u0022 src=\u0022/cms/drupal8-magnetgroup/sites/default/files/inline-images/motors.jpg\u0022 class=\u0022align-center\u0022 /\u003E\u003C/a\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EAre electrical motor faults and failures a prominent cause of downtime in your facility? Then you should be engaging in methods to increase the lifespan of your equipment.\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EIn our latest series on \u003Ca href=\u0022https://www.magnetgroup.co.za/news.php?type=articles\u0026amp;name=LEARN--Condition-Monitoring-part-1\u0022\u003E\u003Cstrong\u003ECondition Monitoring\u003C/strong\u003E\u003C/a\u003E, we\u2019re unpacking the various means of predictive maintenance and equipment preservation. \u00A0\u003C/p\u003E\n\u003Cp\u003EIn \u003Ca href=\u0022https://www.magnetgroup.co.za/news.php?type=articles\u0026amp;name=LEARN--Condition-Monitoring-part-1\u0022\u003E\u003Cstrong\u003EPart 1\u003C/strong\u003E\u003C/a\u003E, we start by reviewing the various benefits of a condition monitoring system, the commonly used techniques and the different types of condition monitoring systems that are implemented.\u003C/p\u003E\n\u003Cp\u003EIn\u00A0\u003Ca href=\u0022https://www.magnetgroup.co.za/news.php?type=articles\u0026amp;name=LEARN--Condition-Monitoring-part-2---Vibration\u0022\u003E\u003Cstrong\u003EPart 2\u003C/strong\u003E\u003C/a\u003E\u00A0and\u00A0\u003Ca href=\u0022https://www.magnetgroup.co.za/solutions-electrical/news.php?type=articles\u0026amp;name=LEARN--Condition-Monitoring-part-3---Vibration-continued\u0022\u003E\u003Cstrong\u003EPart 3\u003C/strong\u003E\u003C/a\u003E, we unpack vibration monitoring. We progress in the series with\u00A0\u003Ca href=\u0022https://www.magnetgroup.co.za/news.php?type=articles\u0026amp;name=LEARN--Condition-Monitoring-part-4\u0022\u003E\u003Cstrong\u003EPart 4\u003C/strong\u003E\u003C/a\u003E\u00A0\u2013 an over view of motor circuit analysis. We end the series with\u00A0\u003Ca href=\u0022https://www.magnetgroup.co.za/news.php?type=articles\u0026amp;name=LEARN--Condition-Monitoring-pt-5---Residual-Current-Monitoring\u0022\u003E\u003Cstrong\u003EPart 5\u003C/strong\u003E\u003C/a\u003E\u00A0- residual current monitoring.\u00A0\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EMotor Circuit Analysis (MCA), as one of the techniques implemented in condition monitoring, assists in preventing downtime by improving the lifespan of \u003Cstrong\u003E\u003Ca href=\u0022https://www.magnetgroup.co.za/solutions-electrical/index.php\u0022\u003Eelectrical motors\u003C/a\u003E\u003C/strong\u003E.\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EIn this article, we give an overview of motor circuit analysis \u2013 the types of testing it involves, as well as the potential faults that it can help to detect.\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003EWhat is Motor Circuit Analysis?\u003C/strong\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EMotor Circuit Analysis (MCA) is a diagnostic technique used in predictive maintenance. It is a de-energized low voltage test method that assesses the health of the motor and the associated cabling. It allows maintenance personnel to pinpoint the exact defects inside the electrical components of motors. A predictive maintenance expert will use \u003Ca href=\u0022https://www.magnetgroup.co.za/news.php?type=articles\u0026amp;name=LEARN--Condition-Monitoring-part-3---Vibration-continued\u0022\u003E\u003Cstrong\u003Evibration analysis\u003C/strong\u003E\u003C/a\u003E or \u003Ca href=\u0022https://www.magnetgroup.co.za/news.php?type=articles\u0026amp;name=LEARN--Thermal-imaging-for-preventive-maintenance-and-safety\u0022\u003E\u003Cstrong\u003Einfrared imaging\u003C/strong\u003E\u003C/a\u003E to detect faults, but these techniques alone may not determine the exact cause.\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003ECan MCA be used on all types of motors?\u003C/strong\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EMCA can be used on both AC and DC electrical motors. MCA can be initiated from the motor control centre (MCC) or directly at the motor. The advantage of testing at the MCC is that it allows for the entire electrical portion of the motor system to be evaluated. This includes the connections and the cables between the test point and the motor.\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003EWhat faults can MCA detect in a motor?\u003C/strong\u003E\u003C/p\u003E\n\u003Cp\u003EAs mentioned previously, MCA is implemented to assess the health of a motor. It assists in identifying the following faults:\u003C/p\u003E\n\u003Cul\u003E\n\u003Cli\u003EResistance anomalies\u003C/li\u003E\n\u003Cli\u003EWinding contamination\u003C/li\u003E\n\u003Cli\u003EWinding shorts\u003C/li\u003E\n\u003Cli\u003EInsulation to ground\u003C/li\u003E\n\u003Cli\u003EImbalances\u003C/li\u003E\n\u003Cli\u003ERotor and back iron anomalies\u003C/li\u003E\n\u003C/ul\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EThese faults are found through the detection of electrical imbalances in the motor and the detection of insulation degradation. Imbalances that exist in the motor will create stray, circulating currents through the motor. These circulating currents create excessive heat in the motor, which accelerates the degradation of insulation. Ultimately, this could lead to inefficient operation as well as ineffective control techniques in certain motors. When a motor experiences insulation degradation, the result is reduced motor life and unsafe operating conditions.\u00A0\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003EWhat are the different types of MCA testing?\u003C/strong\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EMotor circuit analysis consists of online and offline testing. Online testing, as the name suggests, is performed when the motor is operating in normal conditions whilst offline testing is done when the motor is de-energized.\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EMCA online testing is subdivided into current analysis and voltage analysis. Current analysis focuses on the rotating components such as loose or broken rotor bars, cracked end rings, rotor eccentricity, misalignment, and coupling/belt problems. Voltage analysis is performed to identify \u003Ca href=\u0022https://www.magnetgroup.co.za/news.php?type=articles\u0026amp;name=NEW-SERIES--An-introduction-to-Power-Quality\u0022\u003E\u003Cstrong\u003Epower quality\u003C/strong\u003E\u003C/a\u003E issues such as \u003Cstrong\u003E\u003Ca href=\u0022https://www.magnetgroup.co.za/news.php?type=articles\u0026amp;name=NEW-SERIES--Introduction-to-Power-Quality-part-3---Harmonics\u0022\u003Eharmful harmonics\u003C/a\u003E, \u003Ca href=\u0022https://www.magnetgroup.co.za/news.php?type=articles\u0026amp;name=NEW-SERIES--Introduction-to-Power-Quality-part-2---Voltage-Instability\u0022\u003Evoltage imbalances and under/over voltages\u003C/a\u003E.\u003C/strong\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EMCA offline testing is commonly used for the measuring of resistance-to-ground. Measuring electrical characteristics such as impedance, inductance and capacitance will indicate the condition of the windings. The measurement of the inductance is a great indication of turn-to-turn shorts.\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EThe measurement of capacitance to ground determines the amount of winding contamination (water, dirt, dust, etc.). A change in these parameters affects the impedance (total resistance of an AC circuit). These characteristics are measured phase-to-phase, as well as phase-to-ground, and then compared to each other. The percentage change obtained is then compared to the baseline to identify motor circuit defects.\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003EWhy should regular testing be scheduled? \u003C/strong\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003ECertain tests can be performed once-off, whilst others are required to be done on a regular basis to determine the trend and understand the defect progression. It is thus best to test these motors on a set schedule. It will enable you to properly trend these characteristics and gives the reliability program the best chance to identify motor circuit defects.\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003E\u00A0\u003C/p\u003E\n\u003Cp\u003EDoes your facility experience downtime more regularly than you would like?\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EA comprehensive, failure modes-driven maintenance strategy for electric motors will help to reduce costly stoppages.\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003E\u003Ca href=\u0022mailto:hello@magnetgroup.co.za?subject=Electrical Enquiry\u0022\u003E\u003Cstrong\u003ECHAT\u003C/strong\u003E\u003C/a\u003E to us to find out more!\u003C/p\u003E\n", "created": "May 2021", "terms": "Electrical, Education" }, { "title": "LEARN | Condition Monitoring (part 3) - Vibration continued", "nid": "493", "body": "\u003Cp class=\u0022text-align-justify\u0022\u003EWhen vibration increases beyond normal levels, it may be a sign of alignment issues or a source of trouble. In order to avoid costly downtime, you will need fast and actionable answers.\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EIn our NEW series on \u003Ca href=\u0022https://www.magnetgroup.co.za/solutions-electrical/index.php\u0022\u003E\u003Cstrong\u003ECondition Monitoring\u003C/strong\u003E\u003C/a\u003E, we\u2019re discussing what it entails to implement a condition monitoring system in a facility.\u003C/p\u003E\n\u003Cp\u003EIn \u003Ca href=\u0022https://www.magnetgroup.co.za/news.php?type=articles\u0026amp;name=LEARN--Condition-Monitoring-part-1\u0022\u003E\u003Cstrong\u003EPart 1\u003C/strong\u003E\u003C/a\u003E, we start by reviewing the various benefits of a condition monitoring system, the commonly used techniques and the different types of condition monitoring systems that are implemented.\u003C/p\u003E\n\u003Cp\u003EIn\u00A0\u003Ca href=\u0022https://www.magnetgroup.co.za/news.php?type=articles\u0026amp;name=LEARN--Condition-Monitoring-part-2---Vibration\u0022\u003E\u003Cstrong\u003EPart 2\u003C/strong\u003E\u003C/a\u003E\u00A0and\u00A0\u003Ca href=\u0022https://www.magnetgroup.co.za/solutions-electrical/news.php?type=articles\u0026amp;name=LEARN--Condition-Monitoring-part-3---Vibration-continued\u0022\u003E\u003Cstrong\u003EPart 3\u003C/strong\u003E\u003C/a\u003E, we unpack vibration monitoring. We progress in the series with\u00A0\u003Ca href=\u0022https://www.magnetgroup.co.za/news.php?type=articles\u0026amp;name=LEARN--Condition-Monitoring-part-4\u0022\u003E\u003Cstrong\u003EPart 4\u003C/strong\u003E\u003C/a\u003E\u00A0\u2013 an over view of motor circuit analysis. We end the series with\u00A0\u003Ca href=\u0022https://www.magnetgroup.co.za/news.php?type=articles\u0026amp;name=LEARN--Condition-Monitoring-pt-5---Residual-Current-Monitoring\u0022\u003E\u003Cstrong\u003EPart 5\u003C/strong\u003E\u003C/a\u003E\u00A0- residual current monitoring.\u00A0\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EWe continue to unpack vibration monitoring in this article, as we outline when and how to use vibration monitoring on assets.\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003E\u003Cstrong\u003EWhy choose vibration monitoring? \u003C/strong\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EThe need for actionable data in plants and other facilities is typically unquestioned by most reliability and maintenance teams. Where people typically diverge is in a few areas:\u003C/p\u003E\n\u003Cul\u003E\n\u003Cli class=\u0022text-align-justify\u0022\u003EWhen to measure/gather data\u003C/li\u003E\n\u003Cli class=\u0022text-align-justify\u0022\u003EHow frequently to measure\u003C/li\u003E\n\u003Cli class=\u0022text-align-justify\u0022\u003ETechnologies to add to assets\u003C/li\u003E\n\u003C/ul\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003E\u003Cstrong\u003EWhat is a PF Curve?\u003C/strong\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EA P-F curve is used to indicate the health of machinery or equipment over time, to identify the interval between potential failure and functional failure. Wear and tear of a machine naturally occurs with continual use hence the eventual failure of it is inevitable.\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EThe P-F curve below shows the time interval between potential failures on the upper left until machine failure occurs on the lower right. Most assets follow a curve in their lifecycle, from good to progressively worse, until they completely fail.\u003C/p\u003E\n\u003Cp\u003E\u003Ca href=\u0022https://www.magnetgroup.co.za/solutions-electrical/index.php\u0022\u003E\u003Cimg alt=\u0022The P-F Curve\u0022 data-entity-type=\u0022file\u0022 data-entity-uuid=\u0022806f1983-6a92-4554-9b27-a7b26908e316\u0022 height=\u0022303\u0022 src=\u0022/cms/drupal8-magnetgroup/sites/default/files/inline-images/PF-Curve-1.png\u0022 width=\u0022574\u0022 class=\u0022align-center\u0022 /\u003E\u003C/a\u003E\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003EWhat is the importance of the P-F interval?\u003C/strong\u003E\u003C/p\u003E\n\u003Col\u003E\n\u003Cli\u003ELong before an asset fails, it usually begins to consume more energy and lose overall performance.\u003C/li\u003E\n\u003Cli\u003EThe earlier a problem can be detected and corrected, the less it costs to repair (an ounce of prevention is worth a pound of cure).\u003C/li\u003E\n\u003C/ol\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003ECertain technologies have the ability to detect emerging failures long before the asset fails. These are often called \u201Cpredictive technologies,\u201D and are typically part of condition monitoring programs. This is a theoretical framework that may vary from asset to asset, and the point is not to say that personnel should repair a machine at the earliest sign of failure because it may be too early. These early indicators simply signal that additional maintenance actions, such as lubricating the bearings or beginning to plan and schedule maintenance, may help avoid unexpected failures and downtime.\u003C/p\u003E\n\u003Cp\u003EAs mentioned in \u003Ca href=\u0022https://www.magnetgroup.co.za/news.php?type=articles\u0026amp;name=LEARN--Condition-Monitoring-part-1\u0022\u003E\u003Cstrong\u003EPart 1\u003C/strong\u003E\u003C/a\u003E of the series, these technologies include Oil analysis, Ultrasound, Motor Circuit Testing, \u003Ca href=\u0022https://www.magnetgroup.co.za/news.php?type=articles\u0026amp;name=LEARN--Thermal-imaging-for-preventive-maintenance-and-safety\u0022\u003E\u003Cstrong\u003EThermography\u003C/strong\u003E\u003C/a\u003E and \u003Cstrong\u003E\u003Ca href=\u0022https://www.magnetgroup.co.za/solutions-electrical/news.php?type=articles\u0026amp;name=LEARN--Condition-Monitoring-part-2---Vibration\u0022\u003EVibration\u003C/a\u003E\u003C/strong\u003E. Each technology may be used in combination or individually.\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003EWhen should vibration screening be used?\u003C/strong\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EEvery machine component produces a unique vibration signal. Signals displayed in the spectrum often form characteristic patterns. Pattern recognition is a key part of vibration analysis, but significant training and experience are necessary to recognize and read the patterns. Vibration analysis can watch bearing wear across 12 to 18 months as they go from slight wear (no action) to extreme wear (replace bearings immediately). Oil analysis can only be performed on oil-cooled bearings (fewer and fewer are used every day). Ultrasound finds bearing wear too early to replace the bearings (used to know when to grease the bearings instead).\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003ETable 1 below is a simplified overview of the patterns used to recognize the four most common machine faults, particularly in rotating assets.\u003C/p\u003E\n\u003Cp\u003E\u003Ca href=\u0022https://www.magnetgroup.co.za/solutions-electrical/index.php\u0022\u003E\u003Cimg alt=\u0022Table for machine faults\u0022 data-entity-type=\u0022file\u0022 data-entity-uuid=\u00227b8906e0-dbce-41fa-b15f-4e8aec5c8150\u0022 height=\u0022189\u0022 src=\u0022/cms/drupal8-magnetgroup/sites/default/files/inline-images/Table%20for%20machine%20faults_0.jpg\u0022 width=\u0022625\u0022 class=\u0022align-center\u0022 /\u003E\u003C/a\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EVibration screening can identify abnormalities caused by most of these faults as they begin \u2014 in the early stages, providing precipitous warning of impending failure. Vibration screening devices provide quick feedback of the equipment condition by looking at the overall levels of vibration or bearing condition. This will allow for the maintenance team to understand whether there is a problem, instead of performing an in-depth spectrum analysis. The devices look at the entire vibration signal in low frequency, or the bearing signal in high frequency, and provide a single number for overall vibration or bearing condition. If the machine vibration or noise is higher, this value will increase.\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EThe severity of the four common faults can be tracked over time based on the history from hundreds of thousands of machines that have been analysed by many vibration experts over 30 years. This knowledge and experience have been incorporated into rule-based algorithms and a baseline database that have been proven to be effective on standard rotating machines \u2014 motors, pumps, fans, compressors, blowers and single-shaft spindles.\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EHandheld vibration meters can be used for route-based, preventive strategies. A more flexible method is screening with continuous remote, wireless sensors.\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003ERegardless of the method used, vibration technology can provide reliability and maintenance teams with actionable data that can help determine when further analysis is required to decide when steps such as re-lubrication, repairs or replacements should be made.\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003ECatch vibration issues early with vibration data that identifies imbalance, looseness, misalignment, and bearing failures. Do you need advice on what vibration tools and software is best suited for your specific requirement?\u003C/p\u003E\n\u003Cp\u003E\u003Ca href=\u0022mailto:hello@magnetgroup.co.za?subject=Electrical Enquiry\u0022\u003E\u003Cstrong\u003ECHAT\u003C/strong\u003E\u003C/a\u003E to us now!\u003C/p\u003E\n", "created": "May 2021", "terms": "Electrical, Education" }, { "title": "LEARN | Condition Monitoring (part 2) - Vibration", "nid": "491", "body": "\u003Cp\u003E\u003Ca href=\u0022https://www.magnetgroup.co.za/solutions-electrical/index.php\u0022\u003E\u003Cimg alt=\u0022vibration analysis\u0022 data-entity-type=\u0022file\u0022 data-entity-uuid=\u0022e3be24b6-98c1-4bd9-a6e7-b9bda50c6d24\u0022 height=\u0022309\u0022 src=\u0022/cms/drupal8-magnetgroup/sites/default/files/inline-images/Fluke%20Vibration_0.jpg\u0022 width=\u0022465\u0022 class=\u0022align-center\u0022 /\u003E\u003C/a\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EMonitoring machines for \u003Ca href=\u0022https://www.magnetgroup.co.za/solutions-electrical/index.php\u0022\u003E\u003Cstrong\u003Evibration\u003C/strong\u003E\u003C/a\u003E can save you time and money. A machine going offline can impact quality and production. Monitoring machines for vibration issues identifies trends and helps reduce the potential for the machine going offline.\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EIn our \u003Cstrong\u003ENEW series on Condition Monitoring\u003C/strong\u003E, we\u2019re unpacking what it entails to implement a condition monitoring system in a facility.\u003C/p\u003E\n\u003Cp\u003EIn \u003Ca href=\u0022https://www.magnetgroup.co.za/news.php?type=articles\u0026amp;name=LEARN--Condition-Monitoring-part-1\u0022\u003E\u003Cstrong\u003EPart 1\u003C/strong\u003E\u003C/a\u003E, we start by reviewing the various benefits of a condition monitoring system, the commonly used techniques and the different types of condition monitoring systems that are implemented.\u003C/p\u003E\n\u003Cp\u003EIn\u00A0\u003Ca href=\u0022https://www.magnetgroup.co.za/news.php?type=articles\u0026amp;name=LEARN--Condition-Monitoring-part-2---Vibration\u0022\u003E\u003Cstrong\u003EPart 2\u003C/strong\u003E\u003C/a\u003E\u00A0and\u00A0\u003Ca href=\u0022https://www.magnetgroup.co.za/solutions-electrical/news.php?type=articles\u0026amp;name=LEARN--Condition-Monitoring-part-3---Vibration-continued\u0022\u003E\u003Cstrong\u003EPart 3\u003C/strong\u003E\u003C/a\u003E, we unpack vibration monitoring. We progress in the series with\u00A0\u003Ca href=\u0022https://www.magnetgroup.co.za/news.php?type=articles\u0026amp;name=LEARN--Condition-Monitoring-part-4\u0022\u003E\u003Cstrong\u003EPart 4\u003C/strong\u003E\u003C/a\u003E\u00A0\u2013 an over view of motor circuit analysis. We end the series with\u00A0\u003Ca href=\u0022https://www.magnetgroup.co.za/news.php?type=articles\u0026amp;name=LEARN--Condition-Monitoring-pt-5---Residual-Current-Monitoring\u0022\u003E\u003Cstrong\u003EPart 5\u003C/strong\u003E\u003C/a\u003E\u00A0- residual current monitoring.\u00A0\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003E\u003Cstrong\u003E\u003Cu\u003EWhat is Vibration? \u003C/u\u003E\u003C/strong\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EVibration is simply a back and forth movement\u2014or oscillation\u2014of machines and components in motorized equipment. Vibration in industrial equipment can be a symptom, or cause, of a problem, or it can be associated with normal operation. For example, oscillating sanders and vibratory tumblers rely on vibration to function. Internal combustion engines and gear drives, on the other hand, experience a certain amount of unavoidable vibration.\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003E\u003Cstrong\u003E\u003Cu\u003EWhat are the most common causes of vibration? \u003C/u\u003E\u003C/strong\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EVibration can indicate a problem and if left unchecked can cause damage or expedited deterioration. Vibration can be caused by one or more factors at any given time, the most common being imbalance, misalignment, wear and looseness.\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003E1. Imbalance\u003C/strong\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EA \u0022heavy spot\u0022 in a rotating component will cause vibration when the unbalanced weight rotates around the machine\u0027s axis, creating a centrifugal force. As machine speed increases the effects of imbalance become greater. Imbalance can severely reduce bearing life as well as cause undue machine vibration.\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003E2. Misalignment\u003C/strong\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EVibration can result when machine shafts are out of line. Angular misalignment occurs when the axes of (for example) a motor and pump are not parallel. Misalignment can be caused during assembly or develop over time, due to thermal expansion, components shifting or improper reassembly after maintenance. The resulting vibration can be radial or axial (in line with the axis of the machine) or both.\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003E3. Wear\u003C/strong\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EAs components such as ball or roller bearings, drive belts or gears become worn, they might cause vibration. When a roller bearing race becomes pitted, for instance, the bearing rollers will cause a vibration each time they travel over the damaged area. A gear tooth that is heavily chipped or worn, or a drive belt that is breaking down, can also produce vibration.\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003E\u003Cstrong\u003E4. Looseness\u003C/strong\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EVibration that might otherwise go unnoticed can become obvious and destructive if the component that is vibrating has loose bearings or is loosely attached to its mounts. Such looseness might or might not be caused by the underlying vibration. Whatever its cause, looseness can allow any vibration present to cause damage, such as further bearing wear, wear and fatigue in equipment mounts and other components.\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003E\u003Cu\u003EWhat are the effects of vibration?\u003C/u\u003E\u003C/strong\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EVibration can accelerate machine wear, consume excess power, and cause equipment to be taken out of service, resulting in unplanned downtime. Other effects of vibration include safety issues and diminished working conditions. When measured and analysed properly, however, vibration can play an important role in preventive maintenance programs. It can serve as an indicator of machine condition and allow plant maintenance professionals to act before damage or disaster strike.\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003EConsider these variables when analysing vibration:\u003C/strong\u003E\u003C/p\u003E\n\u003Cul\u003E\n\u003Cli\u003EDirection, such as radial or axial\u003C/li\u003E\n\u003Cli\u003EAmplitude, severity\u00A0\u00A0\u00A0\u00A0\u00A0\u00A0\u00A0\u00A0\u00A0\u00A0\u00A0\u00A0\u00A0\u00A0\u00A0\u00A0\u00A0\u00A0\u00A0\u00A0\u00A0\u00A0\u00A0\u003C/li\u003E\n\u003Cli\u003EFrequency, expressed in cycles per minute (CPM) or Hertz (Hz)\u2014one Hz equals one second, or 60 CPM\u003C/li\u003E\n\u003C/ul\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EPlant maintenance technicians need to be able to differentiate between normal and abnormal vibration. A good understanding of vibration basics and the right tool is all a plant maintenance technician needs to quickly and reliably get to the bottom of vibration-related issues, including finding the root cause and severity, then determining the need for service or repair.\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003E\u00A0\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EAre you looking for solution to mitigate the effects of vibration?\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003E\u003Ca href=\u0022mailto:hello@magnetgroup.co.za?subject=Electrical Enquiry\u0022\u003E\u003Cstrong\u003ECHAT\u003C/strong\u003E\u003C/a\u003E to our experts about the Fluke range of vibration testers and software!\u003C/p\u003E\n", "created": "May 2021", "terms": "Electrical, Education" }, { "title": "LEARN | Condition Monitoring (part 1)", "nid": "489", "body": "\u003Cp\u003E\u003Ca href=\u0022mailto:hello@magnetgroup.co.za?subject=Electrical Enquiry\u0022\u003E\u003Cimg alt=\u0022Condition monitoring\u0022 data-entity-type=\u0022file\u0022 data-entity-uuid=\u00221124ef20-b64b-4305-b6d7-3baa02407025\u0022 height=\u0022318\u0022 src=\u0022/cms/drupal8-magnetgroup/sites/default/files/inline-images/condition%20monitoring%20newsletter.jpg\u0022 width=\u0022737\u0022 class=\u0022align-center\u0022 /\u003E\u003C/a\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EEmploying a \u003Ca href=\u0022https://www.magnetgroup.co.za/solutions-electrical/index.php\u0022\u003E\u003Cstrong\u003Econdition monitoring system\u003C/strong\u003E\u003C/a\u003E in your facility can ensure the reliability of your operations. How? By implementing processes to monitor your equipment, you can ensure machine up-time, the reduction in consequential damage to machinery, and the improvement of the overall operational efficiency.\u003C/p\u003E\n\u003Cp\u003EIn this NEW series, we introduce you to condition monitoring.\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EIn Part 1, we start by reviewing the various benefits of a condition monitoring system, the commonly used techniques and the different types of condition monitoring systems that are implemented.\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EIn \u003Ca href=\u0022https://www.magnetgroup.co.za/news.php?type=articles\u0026amp;name=LEARN--Condition-Monitoring-part-2---Vibration\u0022\u003E\u003Cstrong\u003EPart 2\u003C/strong\u003E\u003C/a\u003E and \u003Ca href=\u0022https://www.magnetgroup.co.za/solutions-electrical/news.php?type=articles\u0026amp;name=LEARN--Condition-Monitoring-part-3---Vibration-continued\u0022\u003E\u003Cstrong\u003EPart 3\u003C/strong\u003E\u003C/a\u003E, we unpack vibration monitoring. We progress in the series with \u003Ca href=\u0022https://www.magnetgroup.co.za/news.php?type=articles\u0026amp;name=LEARN--Condition-Monitoring-part-4\u0022\u003E\u003Cstrong\u003EPart 4\u003C/strong\u003E\u003C/a\u003E\u00A0\u2013 an over view of motor circuit analysis. We end the series with \u003Ca href=\u0022https://www.magnetgroup.co.za/news.php?type=articles\u0026amp;name=LEARN--Condition-Monitoring-pt-5---Residual-Current-Monitoring\u0022\u003E\u003Cstrong\u003EPart 5\u003C/strong\u003E\u003C/a\u003E - residual current monitoring.\u00A0\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003E\u003Cu\u003EWhat is Condition Monitoring?\u003C/u\u003E\u003C/strong\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EConsidering that unexpected faults or shutdowns can result in production loss, or even a fatal accident, a process must be implemented to mitigate these. Condition monitoring is a system of continuously monitoring operational characteristics of a machine. It is put in place to predict the need of maintenance, before machinery deterioration or a breakdown can occur. A condition monitoring system provides information about the machine, to pre-empt failures thus reducing downtime. Information such as the vibrations in a machine, its operating temperature or condition of its oil is recorded.\u003C/p\u003E\n\u003Cp\u003E\u003Cimg alt=\u0022CM \u0022 data-entity-type=\u0022file\u0022 data-entity-uuid=\u002209cb9eff-5dc4-40a0-8297-96171f7651e0\u0022 src=\u0022/cms/drupal8-magnetgroup/sites/default/files/inline-images/CM%20Diagram.png\u0022 class=\u0022align-center\u0022 /\u003E\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003E\u003Cu\u003EWhat are the most common methods for Condition Monitoring?\u003C/u\u003E\u003C/strong\u003E\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003E1. Trend Monitoring\u003C/strong\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EThis involves the continuous, regular measurement and interpretation of data. A suitable and measurable indication of machine or component deterioration must be selected. By studying these trends, one can determine when deterioration goes over the critical limit.\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EFor example, airplane engine data can be tracked to detect and diagnose abnormalities in engine performance, leading to the prevention of significant damage.\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003E\u003Cb\u003E2.\u00A0\u003C/b\u003E\u003Cstrong\u003ECondition Checking \u003C/strong\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EThis method involves taking measurements periodically using an appropriate indicator, whilst the machine is in operation. This information is used to measure the condition of the machine at any given time. Consider the example of the use of an oil sight glass in order to check the condition of a machine\u2019s lubricant in real time.\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003E\u003Cu\u003EWhat are the Advantages of Condition Monitoring?\u003C/u\u003E\u003C/strong\u003E\u003C/p\u003E\n\u003Cp\u003ECondition monitoring outputs data in real time enabling the user to determine the root cause of a problem faster. The use of wireless technology on the equipment also connects employees with real time data by using smart phones or tables.\u00A0 The use of this system also enables the plant to go from a reactive approach to a predictive maintenance program, thus showcasing the health of the equipment without the need of additional labour.\u003C/p\u003E\n\u003Cp\u003EIn sum, the advantages of Condition Monitoring include:\u003C/p\u003E\n\u003Cul\u003E\n\u003Cli\u003EReduction in maintenance costs\u003C/li\u003E\n\u003Cli\u003EReduced downtime\u003C/li\u003E\n\u003Cli\u003EExtension of the asset life\u003C/li\u003E\n\u003Cli\u003ECost savings on prematurely changed resources\u003C/li\u003E\n\u003C/ul\u003E\n\u003Cp\u003E\u003Cstrong\u003E\u003Cu\u003EAre there any disadvantages of Condition Monitoring? \u003C/u\u003E\u003C/strong\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EThe downside of implementing a condition monitoring system is, unfortunately, the cost. Sensors, necessary tools, and the labour costs involved in installing the system result in an increase in expenditure. An added cost to train employees to use the equipment accurately and effectively must also be considered. The use of sensors in a harsh environment will also lead to them being damaged and requiring replacement more than anticipated.\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003E\u003Cu\u003EWhat Condition Monitoring Techniques are currently used?\u003C/u\u003E\u003C/strong\u003E\u003C/p\u003E\n\u003Cp\u003EThe conditions below are the most common techniques used presently to monitor machinery.\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003E1. Vibration Analysis\u003C/strong\u003E\u003C/p\u003E\n\u003Cp\u003EThis process is implemented to measure and monitor the vibration level and frequencies of a machine. Vibration analysis allows for the detection of machine imbalance, bearing failures, mechanical looseness, misalignment, resonance and natural frequencies, electrical motor faults, bent shaft and cavitation. Estimations indicate that vibration warnings can provide a lead time of 3 months before a failure can\u00A0happen.\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003E2. Acoustic Emissions\u003C/strong\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EAcoustic emissions are an aspect of vibration analysis, but at a higher frequency than those detected during a typical vibrational analysis. Monitoring these high frequency signals allows for the detection of cracking or impact.\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003E3. Infrared Thermography\u003C/strong\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EIt is a process that uses a thermal imager to detect radiation that is emitted from an object. The radiation is then converted to a temperature, and the temperature distribution is displayed on an image. The process is used to monitor electrical and mechanical conditions of motors, bearings, refractory insulation and the locating of gas, liquids, and sludge levels. Abnormal heat patterns found within a machine could indicate an inefficiency or a defect.\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003E4. Ultrasound Testing\u003C/strong\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EThis process is useful for high pressure fluid situations and both low and high-speed mechanical applications. The shock pulse method is commonly used for condition monitoring. It is a technique that uses signals emitted from rotating bearings as the baseline for efficient monitoring of machines.\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003E5. Motor Circuit Analysis\u003C/strong\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EThis is a de-energized low voltage test method that assesses the health of the motor and the associated cabling. Performing motor circuit analysis on a set schedule can reduce downtime in your plant and increase the lifespan of your electrical motor.\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003E6.\u00A0Oil Analysis\u003C/strong\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EThis process involves analysing the health of machinery lubricants, oil contamination and wear. The process also includes moisture analysis, particle counting, elemental analysis, and acid/base numbers, measuring viscosity and using Fourier Transform infrared spectroscopy to determine other parameters.\u003C/p\u003E\n\u003Cp\u003E\u003Cimg alt=\u0022Oil analysis\u0022 data-entity-type=\u0022file\u0022 data-entity-uuid=\u00227cb19d9b-6a38-4f15-a449-904d056b57fa\u0022 height=\u0022191\u0022 src=\u0022/cms/drupal8-magnetgroup/sites/default/files/inline-images/oil%20analysis_0.jpeg\u0022 width=\u0022339\u0022 class=\u0022align-center\u0022 /\u003E\u003C/p\u003E\n\u003Cp\u003E\u00A0\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003E\u003Cu\u003EWhat are the Different Condition Monitoring Types?\u003C/u\u003E\u003C/strong\u003E\u003C/p\u003E\n\u003Cp\u003EThe 3 different condition monitoring types are:\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003E1. Offline Condition Monitoring\u003C/strong\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EThis type of monitoring is used on assets that are less critical, and where periodic scanning is sufficient to determine the state of the equipment. Offline conditional monitoring is often implemented using both vibrational and oil analysis.\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003E2. Online Condition Monitoring\u003C/strong\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EOnline condition monitoring involves the continuous measurement of an asset by connecting machine-mounted sensors to system software wirelessly. It allows for real-time warnings, obtained from either vibrational analysis, acoustic emissions, ultrasound, or infrared thermography, to be sent out to the respective employees.\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003E3.\u00A0Route-Based Condition Monitoring\u003C/strong\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EThis is a technique that is employed when a technician records data intermittently using a handheld device. It is a method that is used to create a trend pattern and determine if an advanced analysis is required.\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EFrom the above, it is clear that implementing a conditional monitoring system in your plant will increase up-time, increase the lifespan of equipment, and result in a reduction in consequential damage. Follow part 2 and 3 in the series to learn more!\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003E\u00A0\u003C/p\u003E\n\u003Cp\u003EConsidering the implementation of such a system in your facility, and not quite sure where to start?\u003C/p\u003E\n\u003Cp\u003E\u003Ca href=\u0022mailto:hello@magnetgroup.co.za?subject=Electrical Enquiry\u0022\u003E\u003Cstrong\u003ECHAT\u003C/strong\u003E\u003C/a\u003E to us!\u003C/p\u003E\n", "created": "May 2021", "terms": "Electrical, Education" }, { "title": "NEW | Understanding Partial Discharge", "nid": "434", "body": "\u003Cp\u003E\u003Cimg alt=\u0022PD\u0022 data-entity-type=\u0022file\u0022 data-entity-uuid=\u0022a5dbb050-a835-4e7f-a0b3-e51c3c25fbf4\u0022 height=\u0022326\u0022 src=\u0022/cms/drupal8-magnetgroup/sites/default/files/inline-images/PD.jpg\u0022 width=\u0022595\u0022 class=\u0022align-center\u0022 /\u003E\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003EWhat is Partial Discharge (PD)?\u003C/strong\u003E\u003C/p\u003E\n\u003Cp\u003EA partial discharge is an electrical discharge or spark that bridges a small portion of the high voltage insulation between two conducting electrodes or a conducting electrode and earth. Partial discharge can occur at any point in the insulation system, where the electric field strength exceeds the breakdown strength of the insulating material.\u003C/p\u003E\n\u003Cp\u003EPartial discharge can occur in voids within solid insulation, across the surface of insulating material due to contaminants or irregularities, within gas bubbles in liquid insulation or around an electrode in gas (corona activity).\u003C/p\u003E\n\u003Cp\u003E\u003Cfigure role=\u0022group\u0022 class=\u0022caption caption-img align-center\u0022\u003E\n\u003Cimg alt=\u0022Partial Discharge evidence\u0022 data-entity-type=\u0022file\u0022 data-entity-uuid=\u00228770f560-25c6-467e-a070-9933cc0cb4f8\u0022 src=\u0022/cms/drupal8-magnetgroup/sites/default/files/inline-images/What%20is%20pd%202.png\u0022 /\u003E\n\u003Cfigcaption\u003E\u003Cem\u003EVisible evidence of PD\u003C/em\u003E\u003C/figcaption\u003E\n\u003C/figure\u003E\n\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003EWhat causes PD?\u003C/strong\u003E\u003C/p\u003E\n\u003Cp\u003EThere are many causes of breakdown in insulation which lead to PD activity, including design and manufacturing defects, incorrect installation of components, faulty materials, mechanical damage and even vandalism. Even well designed and installed assets start to exhibit PD activity as they deteriorate with age and usage.\u003C/p\u003E\n\u003Cp\u003EEnvironmental factors also play a role in the development of PD activity, including temperature, humidity, atmospheric pressure, vibration and other mechanical stresses.\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003EPD failure process\u2026\u003C/strong\u003E\u003C/p\u003E\n\u003Cp\u003EOnce present, partial discharge ALWAYS tends to increase: but the way in which it increases is both measurable and predictable.\u003C/p\u003E\n\u003Cp\u003EPD activity provides clear evidence that an asset is deteriorating in a way that is likely to lead to failure.\u00A0 The process of deterioration can propagate and develop, until the insulation is unable to withstand the electrical stress, leading to flashover.\u003C/p\u003E\n\u003Cp\u003EThe ultimate failure of HV/MV assets is often sudden and catastrophic. The best case scenario is that growing PD activity causes protection systems to trip out unexpectedly, resulting in outages. The worst case scenario is an explosive release of energy, causing major damage, injury and death.\u003C/p\u003E\n\u003Cp\u003E\u003Cfigure role=\u0022group\u0022 class=\u0022caption caption-img align-center\u0022\u003E\n\u003Cimg alt=\u0022Failure caused by PD\u0022 data-entity-type=\u0022file\u0022 data-entity-uuid=\u00222b7f6c3b-300d-41ab-a627-a376d42c7265\u0022 src=\u0022/cms/drupal8-magnetgroup/sites/default/files/inline-images/Failure.png\u0022 /\u003E\n\u003Cfigcaption\u003E\u003Cem\u003ECatastrophic failure caused by PD activity\u003C/em\u003E\u003C/figcaption\u003E\n\u003C/figure\u003E\n\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003EPartial Discharge Measurement\u2026\u003C/strong\u003E\u003C/p\u003E\n\u003Cp\u003EJust like people, electrical assets age and deteriorate. And as with human medicine, there have been tremendous advances in recent years in the ability to diagnose the ailments suffered by assets in their early stages, enabling us to keep them healthy and productive for longer.\u003C/p\u003E\n\u003Cp\u003EThe revolution in asset management is being driven by two factors which are inextricably linked: new techniques for accurately measuring the condition of live assets, plus new methodologies for managing assets more effectively, based on their actual condition.\u003C/p\u003E\n\u003Cp\u003EThere are many techniques available for assessing the condition of live assets, including oil sampling and analysis, plus thermal imaging. But the most useful is the detection, location and measurement of Partial Discharge (PD) activity in HV and MV assets, which are typically found in substations.\u003C/p\u003E\n\u003Cp\u003EPartial discharges emit energy, the effects of which can be detected, located, measured and monitored:\u003C/p\u003E\n\u003Cp\u003E\u2022\u00A0\u00A0\u00A0 Electromagnetic emissions, in the form of radio waves, light and heat.\u003C/p\u003E\n\u003Cp\u003E\u2022\u00A0\u00A0\u00A0 Acoustic emissions, in the audible and ultrasonic ranges.\u003C/p\u003E\n\u003Cp\u003E\u2022\u00A0\u00A0\u00A0 Ozone and nitrous oxide gases.\u003C/p\u003E\n\u003Cp\u003E\u003Cfigure role=\u0022group\u0022 class=\u0022caption caption-img align-center\u0022\u003E\n\u003Ca href=\u0022mailto:hello@magnetgroup.co.za\u0022\u003E\u003Cimg alt=\u0022PD activity\u0022 data-entity-type=\u0022file\u0022 data-entity-uuid=\u002261a7ff8c-f645-4273-b071-683caa423f73\u0022 src=\u0022/cms/drupal8-magnetgroup/sites/default/files/inline-images/PD%20activity.png\u0022 /\u003E\u003C/a\u003E\n\u003Cfigcaption\u003E\u003Cem\u003EPD activity across insulator voids in Gas Insulated Switchgear (GIS)\u003C/em\u003E\u003C/figcaption\u003E\n\u003C/figure\u003E\n\u003C/p\u003E\n\u003Cp\u003E\u00A0\u003C/p\u003E\n\u003Cp\u003EThe most effective techniques for detecting and measuring PD activity in live assets are based on quantifying:\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003E1. Transient Earth Voltages (TEVs)\u003C/strong\u003E\u003C/p\u003E\n\u003Cp\u003EThe importance of TEV effects (discharges of radio energy associated with PD activity) was first identified by EA Technology researchers in the 1970s. Measuring TEV emissions is the most effective way to assess internal PD activity in metalclad MV switchgear.\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003E2. Ultrasonic Emissions\u003C/strong\u003E\u003C/p\u003E\n\u003Cp\u003EPD activity creates emissions in both the audible and ultrasonic ranges. The latter is by far the most valuable for early detection and measurement. Measuring airborne ultrasonic emissions is the most effective way to assess surface PD activity, where there is an air passage e.g. vents or door in the casing of an asset.\u00A0 Where chambers are completely sealed, ultrasonic contact probes can be used although these are less sensitive than the airborne microphones.\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003E3. UHF emissions\u003C/strong\u003E\u003C/p\u003E\n\u003Cp\u003EPD activity can also be measured in the UHF range, and is particularly useful in monitoring EHV assets.\u003C/p\u003E\n\u003Cp\u003EPerhaps surprisingly, however, detailed PD measurement as the basis of condition-based asset management is still in its infancy in many parts of the developed world, including the USA. Many operators still have no clear information on the condition of their assets until they fail and need replacing.\u003C/p\u003E\n\u003Cp\u003E\u003Cstrong\u003EIn conclusion\u2026\u003C/strong\u003E\u003C/p\u003E\n\u003Cp\u003EThe ability to assess the condition of MV and HV assets by measuring PD activity is increasingly driving a step change in power asset management. At its simplest level, it enables operators to identify and fix faults before they develop into failures. Used to its full extent, it is one of the technologies behind much more effective management of whole networks, based on a fuller understanding of asset condition. The result: greater network efficiency, availability, reliability and safety, with lower capital and revenue costs.\u003C/p\u003E\n\u003Cp\u003E\u00A0\u003C/p\u003E\n\u003Cp class=\u0022text-align-right\u0022\u003E\u003Cem\u003EBy Neil Davies, EA Technology International\u003C/em\u003E\u003C/p\u003E\n\u003Cp class=\u0022text-align-right\u0022\u003E\u00A0\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003E\u00A0\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003EClick here to \u003Ca href=\u0022https://www.magnetgroup.co.za/news.php?type=articles\u0026amp;name=LEARN--The-Value-of-Partial-Discharge-Data\u0022\u003E\u003Cstrong\u003ELEARN\u003C/strong\u003E\u003C/a\u003E about the Value of PD data.\u003C/p\u003E\n\u003Cp class=\u0022text-align-justify\u0022\u003ENeed a PD detection and measurement solution for your facility? Click here to \u003Ca href=\u0022mailto:hello@magnetgroup.co.za\u0022\u003E\u003Cstrong\u003ECHAT\u003C/strong\u003E\u003C/a\u003E to us now!\u003C/p\u003E\n", "created": "Oct 2020", "terms": "Electrical, Education" } ]