Syed Abrar Ali DIRECTOR K ELECTRIC SSUET NED Chairman BoD SEPCO on LinkedIn: 9, Jan 2024, TUESDAY Q: Is Distance Relay used to protect a Transformer… (2024)

∆Z/∆t method in #power_swing detection and blockingImpedance change methods are one of the oldest methods for detecting #powerswing The basis of these methods is based on the #impedance changes (∆Z) calculated by the distance relay.The ∆Z/∆t method is a widely used technique for detecting power swings and blocking #distance_relay s from operating during stable or unstable power swings. The method is based on monitoring the rate of change of the #positive_sequence impedance. This is a method to distinguish between short-circuit faults and power swings on a transmission line. However, calculating the required settings for the power-swing blocking elements can be difficult in many applications, particularly those where fast swings can be expected. Power swings are oscillations in the power flow caused by disturbances in the system, such as faults, load changes, or #generator tripping. During a fault, the impedance changes rapidly and reaches a steady-state value within a few cycles. During a power swing, the impedance changes slowly and continuously. By measuring the rate of change of the impedance angle or magnitude, the relay can identify a power swing condition and block the distance elements from operating. The rate of change of the impedance method can be implemented using different algorithms, such as the conventional method, the zero-setting method, or the straightforward method.The zero-setting method is particularly useful in cases where fast swings can be expected, and extensive stability studies are necessary to determine the fastest rate of possible power swings.it offers a great advantage in its ability to detect three-phase faults that may occur during power swings and allows the protective relays to issue a tripping command and isolate the faulted power system element.#MyDailyQuestion#powersystems #power_system_protection#relay#protection sources:https://lnkd.in/dhfYkaAy https://lnkd.in/di8dQNpA.. https://lnkd.in/dTWVr4u8.https://lnkd.in/dkwnHdCH. https://lnkd.in/dTWVr4u8. https://lnkd.in/dyrPn9wR. https://lnkd.in/dT73HNit. https://lnkd.in/dEq6KPfK.https://lnkd.in/d7f2J5z8. https://lnkd.in/duipV2Jg. https://lnkd.in/dUu_v3Xk..

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-————SAFETY IS NO CHIRP————-The Phenomenon which creates the “CHIRP”, generates a voltage spike greater than 100v Across Terminals of Radio and Flow Computer or PLC , comm port . My ChirpX2 eliminates the conditions that create the Phenomenon voltage spike. This voltage spike is not generated internally of either the Radio or Flow Computer .The phenomenon is generated externally and present in both communications ports and atmospheres. “Safety is No Chirp”,,,,

General recommendation is to properly design and implement the facility’s grounding system to avoid unwanted involvement of ground loops with the operation of the equipment. This kind of approach can also eliminate the need to consider equipment modifications and to engage in costly diagnostic efforts since most trouble involving common-mode noise is avoided in the signal circuits.It is generally not possible in complex systems with interconnected data and signal conductors to avoid all ground loops.Read more https://lnkd.in/gjHG747J

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GUYS! We are using the word "ground" for too many things and it is causing major confusion!!!(I know this isn't a new issue, but a confluence of events made it top of mind for me recently. And maybe extra exclamation marks will help?!?)I gave a short webinar a few weeks ago, and when asked about shield terminations I confidently said that with a few exceptions (fixed facilities and low/audio frequencies), you should always terminate shields at both ends. My interlocutor pushed back on that, saying that a bunch of other recommendations they'd seen said to *never* ground the shield at both ends because you'll get ground loops. Fast forward to today, and I'm prepping slides for a more thorough seminar (through Sierra Circuits--you can still sign up, the seminar is next Tuesday) and this article pops up in my inbox. I click through because I'd just been hearing about ground loops, and upon skimming, this advice stood out under the heading "Mitigating Ground Loop Feedback": "Avoid Multiple Connections to Ground: One of the most common ground loop issues is caused by connecting the shield of a cable to the ground at each end. This will immediately create a ground loop such that any EMI in the area will induce a current in the shield."I don't want to criticize the author, because on closer reading it's clear that the article is in the context of fixed facilities, for instance mentioning that variable soil moisture can affect potential differences at separated points. They're not saying anything wrong, but it isn't as universally applicable as it reads. It doesn't apply to the world of cars/airplanes/satellites where I've spent most of my time, and it largely doesn't apply to mobile devices or a lot of consumer electronics either. I feel like some confusion could be avoided if the standard advice to avoid these kinds of EMI/noise problems was "Avoid multiple connections to EARTH." Again, I know this is an old frustration (as Bruce Archambeault has said for decades, "ground is a place for carrots and potatoes"), but it's unfortunately an evergreen communication problem. Has anyone else had recent incidences of tripping over confusion between ground as earth, ground as current return, and ground as common voltage reference? https://lnkd.in/gcw49GZu

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Enhancing Data Center Protection: The Superiority of Electronic Leak Detection (ELD) over Electronic Impedance and Infrared Testing #electronicleakdetection #eld #roofingservices #roofing

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Meet the DET14C and DET24C Digital Earth Clamps! Designed for precise and reliable earth resistance measurements, these tools are your go-to for ensuring electrical safety and performance. Perfect for professionals who demand accuracy and efficiency in every test.#EarthResistance#ElectricalSafety#PrecisionTools#IndustryLeaders#InnovationInAction#SectorSolutions#SKC#IndustrialSuppliersAndSolutions

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Overhead Power Ground Wire Fiber Cable (OPGW),It is the fourth wire in the power transmission lines and is called the grounding wire.It is used to protect the system from lightning and fault currents, and its operating principle depends on resistance so that when there is any overcurrent, it is discharged through this wire because its resistance is low (10 ohms or less), and the discharge is through copper rods embedded in the ground and connected to this wireFirst function ,It is as a ground wire and is to protect the power transmission lines from lightning that may strike the line as these lightning are high voltage and current and can affect the lines and insulators and thus destroy the glass insulators and damage the plastic insulators, resulting in a separation or trip of the line as the ground divides the lightning current as it is connected to the top of the tower where the lightning current is divided into two parts, each part goes in a directionIt is also used to pass the error current and thus improves the sensitivity of the protection devicesIt also protects the power transmission lines From the high voltage caused by the indirect discharge of charges near the extension of the lines and these charges are concentrated in the clouds, when the cloud charge is negative, an electrical discharge occurs and we have gotten rid of these charges, which negatively affect the transmission lines.The second function of the ground wire isIts use for communications has not been long, as it contains hair wires inside it that are used to transmit the signal and is called opgw (optical ground wire) installed on power transmission towers and extends between stations. It is an optical fiber covered with aluminum wires that are highly resistant to weather conditions, tension and external factors. It is used for communications and data transfer between stations and control centers for the electrical system.That is, this wire has several benefits:1- Leakage of lightning charges through its outer surface (aluminum).2- Its use in communications between power stations through the opgw wire placed inside the core of the ground wire.Dedicated to transfer various types of data related to communications (data, voice, video) and related to control, prevention and monitoring.

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Refer to RED 670 characteristic·Section 1: It is a horizontal line with a slope of zero in red. It starts with the lowest sensitivity value for Differential protection called IdMin and ends at the EndSection1 point, where the Default value is 1.25, a value recommended and set by ABB. Any value can be chosen to control the sensitivity of the relay to differential current.·Section 2: it has a slope of 40% called SlopeSection2 and ends at EndSection2, which is set by ABB with a default value of 3.0. ·Section 3: It has a slope of 80%, also recommended by ABB. RED 670 is also managed through two parts, upper and lower, separated by IdMinHigh. The difference between the two ranges is that the lower region is subject to the rules and conditions of the curve, meaning that if there is a differential fault current Idiff higher than the Curve in the Operate conditionally area, the relay issues a Trip signal. However, if Idiff falls below the Curve in the Restrain Area, Trip signal will not be generated. If there is an increase in the percentage of the 2nd harmonic & 5th Harmonic and exceeds the value set in RED 670, for example, 15% x I 2nd and 25% x I 5th, then RED670 will block the Trip signal to avoid maloperation of the differential protection.·If the differential current Idiff is detected to be very high within the upper region, Operate unconditionally, indicated in purple, which is the area that does not adhere to any conditions for generating the Trip signal. In fact, it is considered as an emergency state where all conditions and impediments are bypassed to generate the Trip signal immediately, without even considering Harmonics levels.·The question arises, what is the difference between Idmin and IdMinHigh? When applying differential protection, one must consider transient conditions during energization, especially those that occur in Transmission lines and Inrush currents built up in transformers. Therefore, the protection engineer must reduce the sensitivity of the differential relay by raising the Idiff setting value to the IdMinHigh value and delay the trip command by setting tIdMinHigh value to allow the removal of transient condition currents, and then restore the sensitivity of the differential protection RED670 to the normal IdMin setting. In this way, it is as if we have adjusted the relay to block the Trip signal command for a a very short period until the system reaches its steady-state. It should be noted that if a differential current Idiff is detected with a value lower than IdMinHigh, RED670 will generate aTrip command after a set time, which is adjusted by the tIdMinHigh element. If the differential current Idiff is higher than IdMinHigh, the Trip command will be issued instantaneously. Check link for RED 670 protection Logic https://lnkd.in/dBXPiZD7 #electricalengineering #differential #protection #highvoltage #relay#powersystems #ABB #KAFD#Neom#PIF

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What To Do When The Operating Temperature Of The Optical Module Is Too High?The operating temperature specifications of optical modules are divided into commercial grade (0-70℃), extended grade (-20-85℃), and industrial grade (-40-85℃), but the most commonly used temperature ranges are commercial grade and industrial grade. What are the effects of excessively high operating temperature of optical modules? If the operating temperature of the optical module is too high, the optical power of the optical module will increase, errors will occur in the received signal, and the optical module may even be burned out, causing the optical module to fail to work properly.

Hear from our experts at the Communications portion of the IA/NE System Protection and Substation Conference, where they will present on a range of topics like field experience with digital secondary systems; innovative approaches for using leased Ethernet circuits; tips for planning, maintaining, and securing critical OT networks, and more: https://lnkd.in/gMmqemZW#otnetworks #dss #substations

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