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If there be a fault during the charging, only the setting of high set elements HS1 and HS2 were there. If the value of the current sense by the relay is more than the set point, the relay generates the tripping command?

– Sel is using two functions at the same time. Blocking (cross block) plus harmonic restraint. In that case, if both functions are working in parallel, and during energization, the relay detects fault current. Or high current in any phase with little or no harmonics. Harmonic restraints func will issue trips without going towards high set or unrestraint.

– What is the DCRP approval?
– For Ministry approval in Oman

– Y 67 function is always +45 degrees?
– Even I also have seen + 30. So it depends on how earthing system achieved

– In a line has underground cables & OHL line together how do they calculate distance setting?
– The total impedance will be ohl+ug
– No, it’s called a hybrid feeder.
Current differential with backup distance protections. distance protection zone 1 should be calculated accordingly from the OHL end.
– I think in this case separate Zone is added to the Underground feeder in order to block Auto Reclosure
– but FO can’t be laid along with OHL
– What if the feeder has more pieces of cable combined with OHL, Where the exact zone can’t be defined?
– Why VFD isn’t contributing the fault current into the system?
– FO can be layed along with OHL. We have Differential protection in line through FO cable

– My relay version is 5.can I use this
– Your relay is pickup still not operated
– CB compartment sf6 gas low in stage 1 or 2.?
– I think the alarm is stage 1 trip is stage 2
– If possible can you change Remote to local?
– Please check the configuration, if you giving a start for UV1. It will not trip, in Siemens Relay, UV will operate when the minimum current setting is off. Please check in this relay also if the Minimum current requirement is there means to make it Off, Otherwise, check any block is given. For example VT MCB Off status like that.

– from the top near the main display 50 operate led and 51 operate led light blinking with red color, so what is the meaning of this?
-Now transformer operates with this condition, and only one feeder loaded with 5 amp only.

– So is any problem arise in this type of condition? And also how to reset this one to get the normal operation?
– If the master trip has operated…just reset the master trip relay and charge the breaker.
– In order to rest LEDs just press clear and go through the navigation

– Can I get the default passwords of 7sj82 & 7ut85?
– available on siemens website

-How do we calculate the tap ratio? Every time shows While I upload file to new relay, may I know what’s problem is?
– Check the error
– Existing file details are
Configuration version: V07.31
Communication configuration version: V07.54
– Use the same version to extract the file other else download offline and then try

– New relay firmware version V 07.54 Can’t connect with a new relay. Not communicate with new relay .. every time failed.
– connect by front port through of 7sj82 relay
– Check if you can see the relay in your online connection. Relay firmware version V07.54 and Existing file firmware version V07.31
Maybe you have a problem with the USB driver.
– It’s necessary to install the same firmware version on your computer
– The Protocols device driver is installed too?

– Line voltage inject 30 degrees lead to phase voltage, Ryb 0 _120 120
– Check voltage across the coil point
– Manual have?
– Check your schematic drawing

– What is the reason for L1-E, L2-E, L3-E voltage higher than L1-N, L2-N, L3-N?
– May be neutral is at some potential higher than earth potential. It is feeding a temporary generator and at the generator, side neutral was grounded
– Maybe that grounding is not proper
-Neutral is not properly grounded, therefore proper reading is coming w.r.t earth instead of neutral.

– How can I change 7UT85 Relay input by DIGSI 5?
– How can I change 7sj82 relay output (NO/NC) by software?
– Through CFC only

– how to update the firmware of GE Relay type MIF II.
– I have a problem with the magnetic balance test in the transformer. lv side magnetic balance is ok but the HV side is not okay?
– Please check proper termination of cables and also check any carbonization at the terminal point

– Then there are any flux leakages inside any core is more as compared to other cores where the winding is done.
– Try to demagnetize the core.
– Connect LV supply to LV side and switch ON & OFF several times say 20
– before magnetic balance which test had you perform
– If vector test or any other test u have performed then this type of error may occur

– If u have done DC winding resistance test then there may be the possibility of demagnetization of core
– How can I do time synchronization through SNTP ON REF615?
– I changed the IP address but the time and date are not synchronous.

– ABB REF615 RELAY -SNTP IP ADDRESS: Is it a new CT or old ??
1) As it is primary wounded CT, insulation fails between primary to secondary windings. Because of voids presence in epoxy moldings.
2) when it is loaded condition, secondary circuits may be opened and leads to high voltage on its terminals which leads to insulation fails on the secondary coil and inter turns fault happened.
– This old one.. and in-cabin we found humidity.
– CT circuit is ok. Because I already checked through injections of current.
– Then in this case more moisture contents are present in primary winding molding portions which lead to such.
– proceed to partial discharge (PD) tests

– anything can cause a flash inside the switchgear itself? which can be found during maintenance?
– all this can be found during maintenance test/troubleshooting/clearance for normally open Bay.
– broken CT / crack on the body/insulation breaks down.
once flash happened no one can be 100% exactly sure what exactly causes the problem inside the SWG parts.
if Arc flash happened to the old switchgear I would inspect and test the other CT inside the substation.

– test CT and visualizy check
– to spare panel / normally open, etc
– CT is not affected by any external impact. Failure happens inside the CT itself

– For these results transformer is healthy and if there is a problem what it could be?
– Red phase Resistance
– What is the problem of the red phase?
– Used new CT’S with new switchgear.
– I think the red phase is dead short
– Why is the second phase to phase and phase to neutral is same value?

– I want to know why you see the red phase is defective
– Have you checked the factory test report?
– I didn’t found it
– But due to physical inspection we saw suite on yellow phase
– It seems the yellow phase flashed
– What about IR value?
– But I am so sure that Y I have the result for discussion
– what is IR?
– Insulation resistance
– Primary and secondary are separate coils
Hv – ground = 18Gohm
LV – Ground = 18 M ohm
HV – LV = 42 G ohm
– RY and BR values are equal
– YB mostly 2 times
– So are PHASE only possible to short?
– If so that would also reflect in ratio, vector group, magnetizing current?
– That is the nameplate of that transformer
– Are you measure these test
– Sorry this is delta winding so
-why phase may open, How you measured these results? By using multimeter or transformers winding resistance measurement kits like TRM or CPC 100 ??
– If you use multimeter secondary value will show a minimum of 0.1 ohms in multimeter but if you use proper testing equipment means values to be in milliohms
– Yes for secondary should use this equipment
– What I think why phase is open hence when you measure YB the result =RY + RB, see even vector group connection diagram
– Actually, if it is star means red short but this is delta so yellow should open
– Multimeter

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– How to download the s1 studio data model from the internet?
– Go to data model manager

– Do you know prive of DIgSILENT Library software?
– Anyone has a 7sj82 device driver V07.50.10?
– You can get Siemens website
– Only available V07.50

– What is the reason of ABTS (relay)function only gives rise to the command to the transformer tap?
– Hello! I´m changing a communication SIPROTEC 4 7SA612<->(RS485)RMC20 RuggedCom<->(RS232)PC to SIPROTEC 4 7SA612<->(RS485)[RS416 RuggedCom]. At SIPROTEC 7SA612 I´m using the PortB with an AME module (pins 3 as RS485 A Signal, 5 as GND, and 8 as B signal). At RS416 I´m using pins 2 as A signal, 7 as B signal, and 5 as GND. Between pins 2 and 7 I´m using a 120Ohm resistor. Unhappily, the new configuration isn´t running. Although, using RMC to convert 485 to 232 before connecting RS416, the communication runs. So, some suggestions to establish communication RS485 between SIPROTEC4 7SA612 and RS416?

– How to calculate fault current with RMS value?
– Inject current a little bit more from Setting value.
– One of my multiline 489 motor management protection relays is having a Reverse Power fault on Generator-B, I removed the relay and installed it on Generator-C, the same Reverse Power fault surface on the same relay, please can anyone help me to troubleshoot this?
– Please check the current direction selected on the relay with respect to the CT Polarities

– Hello Everyone I am a fresher electrical Engineer, Having a problem with the relay connection.
– When we pressing the first Switch our lamp goes on and when we pressed the second switch, the second lamp goes on and our first lamp goes off. When we pressed the Third switch our third lamp goes on and our second lamp goes off. And finally, we have the stop switch Button when we pressed All lamp goes off.

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– Don’t know why I am not getting transformer winding resistance properly? but remaining all tests are ok
– In the same tap I Am not getting an equal resistance value, I m getting RY=89mohm YB=104mohm & BR=111mohm
– Is it testing equipment is calibrated?
– Try measurement with higher current, say 5 – 10A
Test without regulation winding. RY may have some issues?
– Avoid using clamps on nuts or on threads. Clamp it on the main stud.
Make sure tightness in the testing equipment or on the transformer side.
Records the value in the same or nearby temperature.
You suppose to get similar values.

– Is there anyone who has DR analysis material? How to the analysis of any disturbance recorder? how can we analyze fault? Which kind of fault is this or how can we identify the fault?

-Hello everyone. Does anybody know MR tapcon AVR handling?
– When CAN bus communication is cut between master &follower AVR it’s not operating in independent mode. Voltage regulations are not performing.
– Anybody how to view digital events for SEL relay?
– Hello anyone has RET615 abb relay ANSI connectivity package ver. 2.0?
– I have ANSI relay product version 2.0.6. I have installed 4.0.3,4.04 and 5.1 ver But when in the ordering selection tool XC product version is not shown
– Relay ordering code is

– Use update manager and update your PCM
– This all relay one software only acSELerator QuickSet SEL-5030.

– Can anybody help to share the “life assessment report for transformer “ for my reference?
– The configuration online and offline are different, you have to read the device and then start Monitoring
– I want Alstom to make MViec 61850M 61 relay catalog. Anybody has?
– Screw will be there on the sides. we removed both screws but it is not open
– Pull it or put screwdriver at outside and push slowly…shake from all sides..make it softer and open
– Parameter set of the relay should not be higher than the relay template in the Software
– Could someone explain the power management system?
– How to solve this?
– You missed the front panel! Scroll down and you can see that the device does not have a front panel. Drag and drop a front panel liberally and then check the consistency
– What’s cb2?
– What should I do about this?
– Your DIGSI need to have the same P.Set as the device have, So update your DIGSI which is suitable for your device
– Where 2 generators are sharing a network load both are in droop configuration? What would be the effect of manual increasing the speed on one of the generators?
– 1. If the network is grid-connected, the frequency is locked, hence the generator will take more load.

– If it is an isolated system, then system frequency will increase?
However, when 2Gens ate running one should be master and the other should be in droop
-What is droop configuration?
– You’ll find this in the turbine control panel. Generally, For turbine control in grid sync condition or load sharing mode.

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– What is the reason the generator shaft current would be increased?
– Rotor Earth fault with Pulse injection or any other method?
– In the shaft, we have CT and the CT cable connected to the shaft current monitoring device
– Can we able to communicate through a Multimode patch cord on a Single-mode port? anybody knows pls clear me. Insulation failure of rotor wdg?
– No everything it’s OK actually when the turbine rotates high speed the shaft current also increase that I want to know what are the would-be shaft current increase
– shaft current increased means, on load if MVAr is High that time shaft current is higher side if the load is less than rated and MVAr is low u get low shaft current

– What’s mean by cold load pickup protection?

– What is the purpose of this Aviation ball?
– Giving information to pilot that there is a HIGH TENSION LINE. Warning balls for airplanes

– I have some issues with my Siprotec compact 7sj802. I have 3 VT connected in open delta, I set U12, U23, UE based on the connection diagram, but I have Over/Under and General Trip LED. Now I switched off over under voltage function to solve the issue

-Can anyone help me whether the connection type is ok?
What about matching ratio phase vt to open delta vt, it is set 1.73, is it ok?
– Instead of 1.732 put 3, Normal 110/√3, But broken delta 110/3

– Relay shows blocked mode. how can I reset it?
– settings error.
– Device MLFB and disgi MLFB mismatch
– Correct digsi MLFB. U should HV a device file. Not variant file

– Does anyone clarify My CT has 30 VA I need to add AVR Relay so that power consumption is 35VA & intrinsic consumption 1VA above which burden, I have to follow?

– Hi. my relay file has VD address 10003 whereas the relay itself has a VD address of 10001 in Siemens 7UM61. How can I match?

– Hi bro, what is the difference between partial busbar protection and high impedance busbar protection?
– partial you mean Low impedance?
– No.. that one also has high impedance only
– I think connection might be the difference

– What is the origin of the abbreviation KMBG the main switch?
– Please clarify Why ICT requires both sides of V/F protection?
– Anyone test Siemens distance with the double kit?

– For directional relay 67 ANSI feature. What is the angle normally set in the relay? That relay should operate in one direction.
45 degree. Yes. Forward Direction

– It depends on your system. If it is a plain feeder and zero seq point behind your relay then 30deg while if it is transformer feeder with zero seq point in front of the relay then 45 deg
– Thanks. Can you please share its formula how it is decided to be 45
– Zero sequence point in front of and behind the relay means? Can u explain a bit more?

– Under impedance protection testing details with calculation, if have any documents impedance testing
– Does anyone has testing documents for Siemens differential relay apart from the usual Siemens documents(Manual)?

– Could anyone tell me how can I find MTA from the characteristic angle of directional overcurrent relay, because as you know when we testing in omicron we need MTA, but in the relay setting there is the characteristic angle.

– Hi anyone uses megger TDR 1000 /3 fault detector for cable??
– The SQL server error is popping while opening PCM 600 software
– Can u please guide me on how to get rid of it

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The final setting is 85v stage 1 pick up so when I reduced the voltage from 100 until 85V its picked up LED & BO Also but When I need to Chek drop up it will drop up only 101 V
– So it’s showing when the system is healthy to still UV is not reset. So how can I make drop up LED & BO before Nominal voltage 100V
– You want to Decrease the drop-off ratio, this setting will come additional setting check
– My drop-off ratio is 1.2. I think to keep a minimum of 1.05
– So you will get 85×1.05=89.25V
– actually, the secondary of a bushing CT is connected with AVR for OLTC because AVR needs the ongoing load value of a transformer. This means that in case of overloading conditions, AVR will be blocked. So, one CT is enough for giving a response.
– Here in all OLTC, CT is connected in Y Phase only. Is there any specific reason for it?
– Maybe it’s a practice
– AVR is using just to maintain the Nominal voltage. This CT is are using only for measuring purposes. Not protection purpose. So one phrase is enough for AVR
– What is the need for measuring current in OLTC?
-: In AVR CT they are using 2 purpose
1)when current reach 120 % as per customer AVR will not give rise or lower command (AVR BLOCK)
2)circulating reactive current detection That CT is used for winding temperature measurement

– I am going to take the initiative to offer a 100 percent free training course on Autocad Electrical which is one of the most wanted software globally.

Electrical engineer, Dr. Saeed Roostaee with his online training packages about using and working with relays will help you learn to work with relays in the shortest possible time and at a reasonable price.

– Hi, anybody has a tool for making an operating curve for OC, EF, Overflux where I can merge 2 to 3 stage DT/IDMT Related to IEC 618590 protocol. actually, I need to merge Generator Over flux and my proposed setting DT/IDMT needs to merge on the graph.
– Do anyone knows what is the purpose of the Lightning arrester. I know the purpose of surge arrester But need to know why we use lightning word especially lightning is quick, like 50us, and surger is to 200ms to 1000m. lightning has bigger voltage, and surge bigger energy.
– Lightning arrester is used for high-voltage against natural phenomena. a surge arrester is used for high-voltage -Please explain a simple process of how this occurs with an example if possible for you
– Lightning arrester..1)used in buildings is a plain rod with ionizing effect and transmits the high energy to the ground..2) used in switchyards and generator terminals is an NLR device which conducts the high energy to ground, it can also be in a combination of surge capacitor depending upon the equipment being protected.

– What will happen when lightning occurs on a transmission line. Then will it travel to substations?
– OHGW is used to protect T/L from lighting. It didn’t travel to substations, however, each piece of equipment in the substation has a separate bodyguard for lighting
– Then sir why do we use a lightening word for LA If is not protect from lightening ie from the sky
– LA is installed in a substation near T/F. In starting also Means incoming of Line. Sometimes on both sides of T/F. In some, they are only installed on the HV side.
– That’s why the first equipment in swyd where this transmission line ends is the LA to protect from lightning and surges as well.
– Shield wire is also part of the lightning protection system to protect trafo from switching surges

– Why secondary side of CT is shorted?
– How to measure PT resistance???
– With the help of the resistance meter kit.
– Do you mean pt winding resistance?
Yup insulation resistance with the help of megger?

-Earthing should choose from the VT body or another point?
– What is the range (min) & (max) value of insulation resistance?
– Because at secondary side current is hardly 1 or 5A so in that case voltage is too much If we open the terminal there is a chance of the blast
– What will happen when the secondary is open-circuited and your primary is on load, according to the transformation ratio, the primary has to be there is secondary, As secondary is open-circuited, the current will flow through the core?
– As the core has a high impedance, even a small amount of current through it will produce an extra-high voltage which eventually fails the insulation and a short circuit happens.
– So in short never leave your secondary in CT open circuit or lose.
– Any spare core should be shorted
– A PT or VT has its primary resistance (is from the HV tap node to the ground) in the range of 10-100 ohms.

– It is an old distance relay, and it works on the principle of resistance per phase?
– This is not a distance relay. This I’d line differential relay for a short distance with a pilot wire protection system.
– The two pilot wires are calculated with a loop resistance 2*R and a resistor R
– So how can I calculate the setting? any procedure?
– The Instrument transformers do alter the original signal during transformation, so the relay allows for a minimum phase shift during transformation, so the phase shift can be accommodated
– It is a family of the DLN Should give a basic understanding
18/abb pcm600, abb14 –IEC 61850 training Bhatti: I try to do so.
– Transmission line protection by pilot wires (pilot relaying) is limited to 30 to 40 km in route length. For longer transmission lines and sub-transmission lines or even distribution feeders, distance protection is used.
– So they are in theory basically born of the same philosophy of resistance per length of the chosen pilot wires
– This is limited to the pilot wire differential applications.

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– What will happen if one CT sec. star point towards the object and one CT sec away from the object in differential protection?
– The relay will act for external fault.

– I have one question that what is the formula or how do we calculate the arc flash energy values for the specific switchgear?
– There would be a non-zero component of differential current on all phases. t = time duration of the fault
– You may also star towards the object and load. these features can be set in the above-named relays Once it has clocking features, it also has to come with sequence tweaking for they work together to give the microprocessor a sense of rotating.
– DY set the clock at 6 to invert, not o

– Anybody sends an IEEE guide for safety in SUBSTATIONS earthing Testing parameters.
– Can You share any testing procedure and method of transformer testing Pdf?

– I have to replace existing Solkar Rf relays with Numerical relays. What consequences need to face during these modifications? Someone does this job before please suggest a line of actions, logical sequence without interruption of buses.

– What is Digsi 4 & Digsi 5 software? how to use this?
– First of all, you need to install it on your computer. Digsi 5 and 4 are the software we used to configure the Siemens Siprotec relay.
– Can I configure siemens all types of relay to using of this software?
– I don’t think. Digsi is proprietary software.

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To follow, And use the content described and easily talk to engineers around the world.
Electrical engineer Dr. Saeed Roostaee
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– How to simulate protection function using a virtual injection in Vamp255? How to assign the DR in Micom Esergy Studio soft?

– Voltage measurements issue across the output of the charger
– Voltage across the phase- neutral found ok. 120 v. But across the phase – the ground couldn’t be found. Slowly go to zero volts.
– How much is neutral to the ground? What is the charger rating?
– Zero volt
-Maximum current 27.2 Amp
– That is what we call floating voltage, phantom voltage (Ghost Voltage)
-The reason for this is there is no real link between those two points Or there is saturation in the source hence the load loading the source phenomenon
-This can happen if, for example, you are trying to power a 100W 120v rated electric bulb using the output from a source that has a lesser burden let’s say a VT with a 50VA burden
– Check for Case 3
– what is the actual reason behind this issue
– I mean why it happened like this
– If case 1 is suspected Look for a digital multimeter with an LoZ voltage reading range check for potential. If the value is zero still check for Case 2. Short the two suspected terminals through a 2 Amp fuse. If the fuse does not blow Check for Case 3, Look at the burden of the transformer, and test the in-built transformer for coil continuity.
– By which time you would have already found your problem?
– Please note that all the steps have to be done with any multimeter that has the (LoZ) Auto Voltmeter. Start a Private chat with me, if you still need help troubleshooting
– In PCM 600 SOFTWARE unable to read relay. can anyone help?
– It says relay is an inconsistent state. Try again to read from the relay. Make sure u are on the main page of HMI
– Check the IP address. Then relay reset using the power of the relay. Then try to connect hope resolve
– Made Power on/off then the PCM 600 read from Relay
– What are the criteria for min line length protected through modern distance relay?
– I think it can be 100 meters. There are no criteria it’s all about economics and how sensitive the supply is No minimum or maximum length! Notice that during shunt voltage becomes very small and currently becomes very high, hence admittance tends to move towards infinity. But for a very short distance, line differential should be preferred. The 9 members of the matrices can only be compared to the set values by the relay microprocessor as the diagonal members are in theory smaller than others.
– Distance protection zone 2,3 operating time coordination with backup OC n EF protection if not meet grading shall we block the all zones
– Hi. I have one key question that shirt circuit ratings are normally given in 1 sec or 3 sec. For instant 25Ka for 3 sec or may 25ka for 1 sec.

-So how do we choose 1 sec or 3 sec or decide or go for type testing
– The essence of this rating supposedly on switchgear is to know the limit you can push the interrupter to, but it is not good to test switchgear at these values (not that you can get a 25KA test kit) because this would be defeating the purpose of NDT Non-Destructive Testing of the switchgear interrupter.

And for a transformer, motor, and other devices, if Isc is on the nameplate then it is the current that would spoil the coil if it lasts 1 – 3secs. The maximum short circuit would be less than or equal to the rated current times the inverse impedance voltage.

– what is the usual Zone 1 trip time setting in distance protection?
– 0 mS
– How to get Wh values from siemens relay through IEC61850? We are getting only pulse qty
-How about 50 ms Zone 1 distance protection trip time setting?
– Even setting 0, the actual trip will be around 40ms may take?
– Is the relay in circuit/ already installed and in use?
– I try to change some output configuration after that relay configuration error is coming
– Setting File will be stored in the relay, not an error
-Manually reset the factory default setting, then try to ups Lod the same configuration.
– How to do a manual reset?

– How to trigger disturbance records for Binary input of ABB relay. I had configured binary input 2 for disturbance records in application configuration but not triggered.
– Generator pole slip protection regarding document can I get sir?
– Which is preferable to use CVT or IVT?
– CVT is Suitable for the outdoor. Cheaper and used for wave trap (communication between two substations)

– How to calculate Relay setting for differential protection…??
– Old relay was DTH31 with a Bias setting of 15 %
– Now installed RET615 relay.
– How to calculate new settings?
– Numerical Relays, No need for this type of connection.
– Replacing relay panel is existing substation.
– Can’t change CT on both the side.
– May I get any documents where have pole slip testing procedures are available. please. Please share these books.
– Nothing to share just cover pages
– Hello Partners. I need a favor from you about software to use Sepam Serie 20 Relay, please
– Don’t switch the supply off for this relay otherwise it will damage
– What is the circulating current in parallel transformers?

– What is the suitable differential setting?
– could you suggest to me which brand is better?
– Eltel Or Doble CPC 100/ TD12 is the best. M4100 Doble year kit is rugged

-what is that CTM?
– lotting machine
– what is the meaning of the BR.D reading I got from the Megger insulation tester?
-Bridged connection between life and earth

Dear engineers, you can share your related issues in our discussion groups to find out the solutions. Please text on WhatsApp to join (click)

– Someone, can you help explain wet/dry contact?
– With voltage/potential it is called wet contact. Does anyone have to cost data of medium voltage submarine cables?

– Anybody knows about the dielectric strength test of oil used in transformers
Kindly share about its minimum acceptance result standard if any?
– Yes tried but nothing displays that’s why I ask?? Could you tell me the default password??
– 2 for configuration change
– You can reset from relay only.
– First of all go. relay default front page then -> then give password down key and reset (ok)
-Actually, I reviewed the manual it was written 4digit password but didn’t mention password accordingly we just tried 0000, 2222, 4444. These three also passwords are incorrectly shown.
– You communicate with pc? Default password 2 for configuration change/ 1 for operator
– Only 2 password
– No just by hand
– Ok. Press only 2

– Can anyone share an SLD for protection?
– Please share the full version pdf of IEC 62271-200&100
– Anyone can share IEC 61643?
– Does anyone have any testing procedure for Ziv relays

– Can anyone share your area panel scheme which shows DC control supply distribution and how redundancy is achieved for control supply in case of failure of the one?
– This is a good system as it parallels feeding and it will not be in if one of the power supply get trip
– Did anyone noticed a dc voltage spike at the output of the diode assembly? due to multiple dc earth faults.? Actually, in my system, 4 blocking diodes are being used. Two earth faults occurred simultaneously in the system, first earth in source-1 +ve branch and second earth on source-2 negative branch due to which system voltage got doubled to 440V
– Did anyone went through such kind of situation?
– Is there any difference between core balance CT and Toroid CT?
– Some Toroid CTs are used for core balance measurements because those ones have very high sensitivity & resolution.

– Please share the practical Earthing book.
– Does anyone have ABB SPAJ 140C or 150C operational manual. please share
-Please send a differential relay Calibration test report format.

– Can we install/retrofit the ERMS switch in the existing LT swgr panel?

– Who has experience with microgrids here?
– Distance relay test procedure please by Omicron without OCC
– You should do it yourself because there would be peculiarities to your system not in mine
– hope you have a CMC kit and a license file?
– Do have any calculations for RIO Graph .. please share

– We are having random tripping of Terasaki ACB (ARS216S) which is connected on the primary side of the step-up Tx (415/6.6kV) which eventually is causing to trip all the GCB’s connected in parallel to different gensets. Any idea what can cause this issue? The sec side of the TX is HV VSD which is running absolutely fine without creating any issue.
– Tripping is immediate after startup?
-No. The system sometimes runs for even half an hour and then just trips for no reason without even introducing a new load
– More. ACB should have a built-in event recorder. It will give you cause and time of tripping
-How to download that? Is there software or something?
– Try step by step to analyze and move forward to correct
– No. It should have an LCD display that shows real-time current. Configuration settings and the event history of ladt tripping
– Can you share its screenshot or video
– Yes correct. Will ask for the photos once it will occur again. Right now the system is working fine for almost 9hrs

-Quick CMC through Distance protection test possible sir? Or advance Distance module required for the test?
-Testing is possible, but need to manually calculate the current and voltage value for a specific impedance, in quick CMC.
– May I get manually calculation of Impedance
– You can select directly impedance instead of Voltage & Current…option available…
– Distance protection test report may I get sir? Calculation of distance protection may I get sir? Please share.
– Artificially Line Ground fault created on Raigarh puglur HVDC to tune relay settings.
– Always theoretical & assumption workout may not gives accuracy. Sometimes needs to be tune in a practical way
– I saw firsthand something like this go wrong, and it was fatal
– I am working in HVDC Raigarh and this line fault is tried several times in the commissioning period to get accurate tuning of the online dc line fault locator.
– I know it is really dangerous to carry out the line fault successfully
– There are remote controlled projectile devices, so try to be on a safe side
-: How actually is that fault created?

-I need this relay technical manual anyone has kindly share with me
– Is it possible to share ur valuable advice on the following concern. Resistive/impedance reduced fault happens when the fault is not happening at the first bus, say after x km of line/earth. Recall that the line has intrinsic properties of ( y + j z) ohm/km. Also, there is an intrinsic resistivity of the earth which increases its resistance by distance R = pL/A
– Why do we need DEF protection in distance? But 87 cannot detect Internal faults? Is REF more sensitive as compared to the differential
– I read somewhere that phase-to-ground faults are highly resistive, and to clear these faults we need more sensitive protection like DEF?
– SEF not DEF
– I think he’s asking about the Directional Earth fault
– 87 detects internal faults on phases
– Yes I am asking about DEF also which is mostly used in distance relays for transmission lines
– What’s the stability test? How can perform for 66 VK substation?
– Please send the method procedure for this test.
– When the energized line comes in contact with a grounded thing like a tree branch it finds its path through the ground back to the substation. Because the magnitude of the current may not be enough to offset the 0.1 – 0.2 I> set for earth fault, it detects only through the NGCT a negative feedback current more like the SBEF but it monitors when there is a reverse from s2 – s1
This means DEF is used because it is used primarily for phase to ground faults and is more sensitive to Ph-G faults?

– Anybody knows about the multi-stage series power filter?
– There is no potential difference hence no effect
-No. due to the complete cycle.. neutral should be needed.
-Consider Phase to phase then?
– I guess. Phase to phase, it will come as shock as the circuit is completed
– It will be a short circuit
-This person will get electrocuted based on the condition of his hands (ie., Surface resistance) and his body resistance… Pls remember the step potential diag, with differences, the earth is replaced with conductor and legs with hands…
– We need to know the cable impedance per meter, the current flowing, and distance hand-hand
-Voltage drop is negligible. See also resistivity of aluminum vs soil resistivity

Join 20 WhatsApp groups for protection engineers

  • WhatsApp Grp 01: Protection Relay – General
  • WhatsApp Grp 02: Substation Automation – General
  • WhatsApp Grp 03: Transmission line protection
  • WhatsApp Grp 04: Transformer protection
  • WhatsApp Grp 05: Motor protection
  • WhatsApp Grp 06: Generator protection
  • WhatsApp Grp 07: Overcurrent and Earth Fault Protection
  • WhatsApp Grp 08: Busbar protection and Bay controller
  • WhatsApp Grp 09: Breaker protection and control
  • WhatsApp Grp 10: Protection Relay Testing and commissioning
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  • WhatsApp Grp 13: PSCAD
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  • WhatsApp Grp 16: GE Relay Configuration
  • WhatsApp Grp 17: SIEMENS Relay configuration
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– How can calculate the Vector group of CT?
– CT doesn’t have any VG
– However, they do have minimal phase shifts
– Just D or Y connection depending on the application?
-basically, this CT used for Differential protection. Star is best for the object to be protected. Star point on all s2 for HV CTs. Star point on all s1 for LV CTs
-This is center taped so s3 for full ratio or s2 for half ratio

– Does anybody assist what is slope value for the single side-feed line? I saw the manual they didn’t mention value. Is there any fixed value for that slope? In setting also didn’t find value for that single feed value.
– Slopes are calculated! And it is the boundaries that set trip areas and operating regions. What is your operation criterion?

– When I want to test different Protection for DYN11 using quick CMC how much the angle of secondary current when I use 0 angles for primary side current certainly for the same phase.
– For Dyn11. 180+30=210 & balance angle Should be applied in LV side
– why +30 for 11 I guess it is – 30
– -330(CW)=30(ACW)
– Why use quick CMC? When you can use Advanced different operating characteristics?
– Try any of the two and just input your system parameters for both test object and system. Omicron would do the rest for you.
– Actually, as you said it is better but there was a problem. When I open diff characteristic the connection between CMC and pc interrupted
– Have you ever had the same issue? Actually, I don’t know the reason

-What CMC model do you have?
– Cmc 356
– Okay then you should be having RJ45 Network cable
– When I use OC. quick no problem When I use advance diff the problem occurs
– Download the latest model of Test universe and install it. Most likely your antivirus engulfed some registries that contain omicron executable files
– Deactivate it when installing and reactivate back shortly after. Check if u have a license for advance differential

– How to test current reversal and power swing in p546 micom
– Kindly how to test differential really using quick CMC

Protection Relay Discussion Group on Telegram:

– help please by checking to debug online in PCM ABB REL670 is showing block input 1 to its all protection what can be the reason?
– means block input is 1 there is nothing attached to it but it is 1 and no function is tripping

– Anyone has an idea in EF19 thermal overload relay make abb While testing relay operating less than setting current (that means 75% of setting current)?

– what‘s the reason for Using the function 59N and if necessary creating a ring loop for all my relays in the SWGR??
– Do you have information about C&P in Substation?
-132kV, 24MVAR Capacitor Banks (group 1 & 2 = each 12Mvar, 8MVAR/phase) when tested on-site by applying three phases 400V give acceptable values of 318mA on each phase thru clamp meter.
– However, when group 2 of the blue phase was intentionally cut off for testing purposes, it showed the following suspicious result? (instead of 318mA)
Blue: Group-1 160mA (normal) and group-2: 0A (acceptable value)
– What is the reason behind 290mA values for red and yellow? It shouldn’t be 318mA?
Anyone, please
– What could be the solution for the above error
– Is it over Ethernet or Front port
– Also you can ignore the error. In the case of the front port try with Moxacable
– Schneider Recommenda Moxa cable for front port communication. It’s with Mona cable and front port
-What is the communication port number your using?
– Can you send the photo of the device manager moxa driver settings?
– Use com1 for communication. If still not able to send a file, try to send the required parameters only. Open setting file, say you want to send VT PRIMARY, then click on and send data to the device

– If Anyone has a 7sk80 thermal overload calculation sheet pls share
-While extracting disturbance recorder in Micom p643 relay, we have this error operation failed?

– In my power plant, DC system +ve is solidly earthed. Checking it through megger to make the BGFT kit but am now able to locate the fault. Due to a system running I cannot switch off the dc controlled feeders. Can anyone suggest to me any other option, idea, or any other kit through which I can get the help.?
– Megger BGFT is the best way to locate the DC ground fault without switching off DC circuits, u just need to measure the impedance from the main source until reaching the branch circuit that has the fault
– But it is failed at my location to trace the fault. As per OEM due to complex DC circuits and the use of electronic cards in breaker feeders is not allowing the kit to trace. But this should not be the reason. Looking for some more options to identify
– I have a question for everybody, Anyone has a document or example for cargability of CTS?
– I am doing testing for sepam87T, diff function does not operate but other functions in the relay are operating. I tried to fix this issue by activation output and led but still not working. The relay read current on both sides and read diff current but there is no output
– I didn’t check sepam87T. CT Matching Factor (ICT) Star point of the CT connection Vector connections of TR While injecting dual Current, check the phase angle magnitude /Compensation.
– Check output configuration, And Confirm any Blocking signal generate due to Breaker feedback / CTS…
– Actually, I checked the output configuration. What do you mean by blocking? For Example 3 Wdg differential, only you are injecting Two Wdg, Third wdy CTS may Block the output But Function will work…

– Can anyone help me to resolve this issue, I installed PCM for the first time.
– can you see some QR codes in IED?
– No, nothing like this on IED
– 220kv Alstom china, breaker drawing required, kindly share
– Hello! Suggestions to power simulators instead doble or omicron?
-ISA. DRTS series from ISA

– Crowbar failed alarm was triggered in my AVR system (ABB UNITROL 5000) and the same got reset automatically. failed alarm triggered. Can anyone tell me the actual root cause to avoid in the future.?

– Do anyone has Abb REF 541 relay operational manual please share it with us
– Can anyone please tell me the testing procedure of low impedance busbar protection for 132kv single breaker double busbar protection?
– Let’s see your single line first
-Next step?
– Testing procedures can have peculiarities. I would give you the testing procedure if I see the power flow / single line.
– Loss of Excitation of generator protection test process or calculation may I know sir .. please share related documents.

– 90% stator earth fault protection Test process please share with me.
– Have any process. Voltage injected in relay PT coil but not trip. What is the protection operating criterion? Is it only open delta voltage-based or NGT voltage-based or both?
– Open delta voltage based
– Inject normal voltage in any one phase of terminal pt so that no VT alarm came. Then inject in open delta pt and NGT as setting values. It should trip
– Setting value 14 volt
– Anyone can give an idea about starting auxiliary relays manufacturing?
-Setting value injected Ji .. but not coming trip /alarm
– Is there any other ct or vt alarm coming during voltage injection?
– LV BCT can’t be ignored for REF. For LV side BCT is mandatory for REF SCHEME
– So anybody has used IPCT? What are its consequences?
– These connections might be possible when one of the windings of t/f is delta connected (like dyn11, ynd1, etc.) but these connections can’t be made on auto t/f
– So, you mean either higher values or IPCTs should be used for mismatched REF if it is connected!

– Anyone has a CGI14S manual?
– Can someone please help me with the soft copy of NEC2020
– CG relay communication software anyone has?
– Default password..?
– 000000
-For 7UT51?
– 6time 0

-kindly find below the steps to restart the 7SR relay Switch off the relay.
– Press and hold the TEST / RESET key (continuously until the startup menu display) and switch on the relay supply.
The display will appear startup menu. Select cold re-start or warm re-start. Please check and update the relay status after re-start.
– In 7SL86 line differential relay charging current compensation setting is mandatory for local and remote end OR only local end?
– Please share the Scope of work for Numerical relay testing and frequency.

-Does anyone have a power transformer acceptable error limits of its testing like winding resistance, ratio test, etc.
– What is the purpose of using TPY accuracy class CT?
– Check the device specified tech norm applied
– Hi. Can someone confirm on Energy Meter accuracy testing of.0.2 and 0.5? What test equipment is used for this testing?
– Please confirm
-CMC 356 Omicron

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One of the common applications of GOOSE messages is to implement a ‘fast bus’ or ‘reverse interlocking’ bus protection scheme. In its most basic form, a directional overcurrent relay is installed on the incomer. If a fault is detected towards the bus the incomer relay will trip unless any of the feeder relays send it a blocking signal indicating that the fault is external to the bus.      

Reverse Interlocking Scheme

Ideally, this type of scheme should be tested by primary or secondary injection into both the incomer and feeder relay at the same time. However, there are often cases when access to only a single relay at once is possible. Since IEC61850 is an international standard, the use of a third-party test tool is possible. One such test tool is the OMICRON CMC.  

The relay-relay GOOSE application is created in DIGSI IEC 61850 System Configurator. The pickup (‘start’) of the overcurrent elements in each of the feeder relays is mapped to a GOOSE input in the incomer relay. The configuration is via drag and drop – DIGSI automatically takes care of the necessary low-level details of the protocol.

DIGSI IEC 61850 System Configurator 

If the GOOSE mapping has already been created in DIGSI, then getting this information into the OMICRON is as simple as exporting the Substation Configuration Description (SCD) file from DIGSI and importing it into the OMICRON GOOSE Configuration software. 

Export DIGSI SCD file, and Import in 2OMICRON GOOSE Configuration 

By connecting the OMICRON into either the subnet or directly into a relay, the OMICRON software allows the CMC to either simulate or subscribe to any of the stations. Again, the configuration of this is via drag and drop – the relevant goose data-set item is selected and mapped to a binary input or output of the CMC. These are then available for use as standard binary inputs/outputs in other parts of the Test Universe software. 

GOOSE data set mapping

By use of the Omicron secondary injection combined with its GOOSE functions each of the SIPROTEC relays in the fast-bus scheme can be tested individually.  

Test 1: Testing a feeder relay:

Testing of the feeder relay is to confirm that as soon as its overcurrent element picks up it transmits a suitable GOOSE blocking message. The Omicron is connected to inject a secondary current into the relay above the element pickup threshold. The Omicron is set to subscribe to the ‘Start’ GOOSE message expected to be transmitted by the relay. Since the SCD file was directly imported from DIGSI, all the protocol details of the GOOSE message will automatically be checked during the testing for conformance with what the incomer relay is expecting.
An Omicron test is created and executed to record the time taken from the injection of current to receipt of the GOOSE message. Typically times expected will be the pickup time of the relay element plus just a few milliseconds.

Testing Feeder Relay – confirming GOOSE message dispatch

Test 2: Testing the incomer relay 

The incomer relay is tested to confirm that when it receives a blocking message via GOOSE that its directional overcurrent element does not issue a trip (Figure 7). The OMICRON is configured to simulate the GOOSE message that would come from one of the feeder relays. For testing, activation of this GOOSE transmission is via any of the mapped binary output functions of the Test Universe application (Figure 6).
Using the State Sequencer, the first state can be set to inject voltage and current into the relay without any GOOSE message transmission. After a short time delay (to match that recorded in Test 1) the second state should keep the analog signals on, but activate the GOOSE message transmission by turning the relevant binary output on. A successful test is where the relay element does not trip.  

Using a binary output to generate blocking GOOSE message

Testing Incomer blocking with received GOOSE message