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sample discussions


– while I connect sip 5 bcu like that error I got. how can I solve that
– Differential initial setting is 0.2*In?
– What is the meaning of it?

– Anybody has breaker dcrm result & procedure for testing breaker dcrm with megger TM1740 kit.
– I think the problem is your RAM
– maybe you can upgrade it to 8GB or 16GB.


– What is this problem?
– Install the device driver for 7sj80
– My breaker got tripped on differential Relay is not showing any current
-87BD In phase R, Y, B But no current
– W1 or W2
– It’s tap changing problem
– It is due to an imbalance of voltage
– Tap was not changed. In relay 5th harmonic and 2nd harmonic is blocked.
– Not showing any winding
– I just updated the firmware of my 7SA82 relay from 7.82 to 8.06, now the relay shows firmware 8.06 but CFG 7.82, when I go to the device information page of offline extracted settings, here upgrade option is missing at configuration version, please guide me how can I get upgrade option


here you can see, upgrade option is not there near CFG


this is what the manual shows, but in my case, this upgrade option is not there as you can see in the above picture.
– Did u import the communication firmware for this device?
– issue resolved, by following this “You can go to “Upgrade project device” in the project tree, and you will find for upgrade CFG”

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– Getting this error when installing digsi 4.94, plz help
– When I am taking megger for pt primary to secondary, then when taking b/w primary and 1a and primary getting 400 Mega ohms, and primary to 1n getting 1.9 Giga. Ohm, why is the difference?
– What is the applied test voltage?
– 5kV
– Remove secondary connections either connected 1a or 1n. Apply test voltage case1: primary to 1a
Case 2: primary to 1n. The values more or less should come the same. Sometimes it will show some difference due to testing machine (Megger) measurement and also ambient temperature(T)
– IN the 7SR relay where to find the Characteristic angle?
– Using reydisp evolution
– take pri. to earth at 5kv and seco. to earth at 500 v
– Anybody tested the GIPAM 10NZ relay? Where is direction selection for 67G SGR Protection In software?
– Check-in current protection folder
– +-45 by default

– any ziv zlv distance protection engineer urgent need, Unbalance settings are given 30%
– How to test and justify this 30%
– How to Test 100% Stator Earth fault protection?
– With 3rd Harmonic. It is the power setting. When u give the fault with power above 30%. Then only the relay will be active.
– Which relay Model?
– 7UM622
– Control cable length is 700mtr, then how to calculate voltage drop.

– if 220 kv or any kv panel which receiving end panel thus their relationship angle between v-i is 180 degrees apart.? is this right?

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– Vph to Vph selected. The setting is 121 V
– Then for secondary injection how to inject?
– How to test under excitation protection in Siemens relay 7UM?
– U have to first take the capability curve of the generator and then on under excitation side make 3 part one at 0deg angle, 90deg angle, and 120 deg angle
– For each angle, u will get a certain MW and Mvar which u can inject through ur secondary injection kit in terms of voltage and current?


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– Can anyone provide the DNP3 protocol standard?
– On the upper side of Relay Ready LED is Blinking. That’s why it’s not communicating by software, How to fix it
– which led?
-Ready LED
– relay faulty indiction is going on annunciation.
– No annunciation is coming on other. but I think the relay gets faulty.

– Is the relay restarting again and again? Because it blinks when in test mode
– Is it in test mode?
– Is it rebooting
– u can also check the error code in the relay
– Not rebooting
– HMI working properly
– When you read the data from relay through software what error it is showing?
– oh ABB show on the display
– this is an error inside
– Not communicating with software
– must repair
– What is the fault code relay is showing?
– Not showing any fault Or warning code, the Only ready LED is Blinking


– Now communicated with relay, But the Blinking problem is not fixed
– Go to main menu/monitoring/IED status/self-supervision, Check for the faulty hardware module. If it is a diagnostic failure then also it flashes
– Check IRF alarm contact status to find the reason, It is an internal fault maybe.
– Why is current in the R phase so much high on normal voltage
– Load on the R phase might be more as compared to other phases.
– Normal voltage is injected, And the normal current is injected.
– whats the ct ratio?
– 400/1
– check backup relay measurement
– how many the core in ct?
– But I am injecting to relay directly
– how secondary set Check ct wiring?
– Star point of relay Input Is correctly wired
– star point is only for protection
– R u injected or the line is the charge?
– Relay is separated from PT CT, I am injecting current from omicron.
– PT as well
– R u injecting balance current?
– 1 A
– Yes
– check ct ratio in the relay.
– CT ratio is OK in the relay when u injecting is there any current in IN?
– Yes same as the R phase.
– Check-in this, it was fluctuating
– inject only r phase backside of the relay terminal not on tb
– It’s 934 A is showing when I inject only in R phase
– led is blinking for this relay (REL670)


– Is circuit breaker contact resistance temperature-dependent
-Yes the hotter it has the higher the value. That’s why you would have seen that the current is injected for a very short duration. As not to elevate the temperature
– Does variations in input voltage affect breaker timing?
– Input supply varies from 110V to 170V. The ideal voltage is 110 V

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-: 132 kV breaker close time =77 ms
– At160V
– PT ki 110 v vary kr rhi h
– No pt
– Direct supply from AC source for testing
– ac supply for the kit, No for breaker control supply
– Usually, the higher volts may not affect the timing but will damage the insulation of the coil
– Is this value is acceptable
– ac supply use in break only for motor. Refer to the manual.
– Input ac supply for the kit is 260V For MV, I have less than 60ms for one while 40 ms for the other type. The source is giving 260 V
– So you have to compare with the values in manual
-Trip time is 46 ms, CO=39ms
– please check these angle diff. is correct or wrong?

– Can you tell me what is the name of this marked portion? And why it is connected there?
– It’s correct, inductive.
– When I charge the 132kv line, then I get the all secondary 3phase voltage at the panel TB from line CVT. But I trip the breaker, now the line remains back charge bcz of opposite end connected. In this case, I get only R, B phase voltage from the same line CVT. Y ph voltage is near to zero(i.e, y=7 v) How it is possible?
– line pt install
– May Y phase jumper opened in transmission line?
– please check from the remote end voltage
– It also perfectly correct. remote end all three voltage is perfect?
– tell me all three voltage
24abb , 18:32 -abb pcm600: R=63.8
Y=63.03
B=63.35
– Now it is charged at both ends. When I cut our end breaker, then I get only 2 ph voltage
– r u seeing in the panel?

– No seeing at pt MB
– cut the break from remote end charge from our end then check
– same problem
– I get all 3 ph voltage
– It is clear
– CVT after breaker or before when charging from both ends then what about the load
– all three loads are balance
– Does the problem solved now? Check the wiring of pt at tb
– Is it loose
– It is perfectly connected
– What about pt secondary phase to phase voltage?
– 110 if it is charged at both ends
– What about all other phases?
– All three-phase to phase voltage is 110 if the line is charged at both ends.
– If I cut my end breaker then I get 2 phase voltage only
– I am not getting Yph voltage

– Does the LA inline side shows leakage current?
– If our side is charged and the other side breaker is off in this case I get all three-phase voltage
– Yes check for leakage current in LA.


– Does DNP communicate over RS 485?
– Yes, if supported by the relay manufacturer.

– Correct, RS485 RS232 RS422etc is just a standard for serial communication
– DNP is a protocol that can be communicated over RS232 or RS485 serial port. DNP can definitely be daisy-chained, just use a terminating resistor
– The motor got tripped on 51n but all three-phase currents are equal, the protection on the calculated value of three-phase currents internally by the relay. the relay was 7sj66. What are the causes?
– IR value of the motor is good

– Anyone can explain the difference between DNP and Rs 485
– RS 485 is port, DNP is protocol, DNP is a protocol
– Used in the process automation system
– Anyone can explain how to collect ABT meter load survey data through RS 485 port?
– Ok thanks, so the DNP3 outstation address will act like node ID?

– How many relays can we drop on an RS485 using DNP3?
– I mean DNP3 slave address ranges up to 65535
– The maximum IEDs that were successfully daisy-chained was 255, however, I won’t use anything close to that.
– Read through the RS485 standard, all is specified, this is not my area is expertise, but I’ve seen them work over 200m, use a 9600bd 2 wire comms, With 2 pair, 0.5 twisted shielded pair, proper earthing of spare wires and shield, I used till1400 meter closed loop
– anyone uses kocos Artes 440 three-phase secondary innection set.

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– Please share a detailed explanation of under excitation Protection
– Please tell me about the LBB scheme in 220kV
– Local Breaker protection scheme basically depends on the type of busbar scheme you applied for.
– What is the type of bus bar scheme used in your 220kV station
– It is a trip matrix for designing protection schemes
– For which type of unit? Is it for generator
– Class A is for Turbine trip class B is for the GCB trip
– Whenever Turbine tripping occurs, GCB trips consequently.
– No correlation with a generator in this case. It is for a transformer. The above transformer is a GT.
-Though it is a GT, protection group A and Group B is for transformer breaker itself. Hv side and LV side (GCB), 86.1 & 86.2
– GT doesn’t have HV side CB. 86 means Master tripping. I’m saying for transformer
– Here in the trip matrix, Group A & B are categorized for master trips only.
– You mean, GT doesn’t have hv side CB
– Sorry LV side doesn’t have CB I meant to say. if it is 11/33kV GT. CB will be at the 33kV side in small power plants.
– It is a transformer
– I want a wrt generator For the 7UM relay.
– Low impedance busbar having main and check zone For busbar trip. how this is working?
– I understood the scheme is a double busbar with a transfer bus scheme.
– The main and check zone concept is different from LBB. We use a zone system in busbar differential. Whereas, LBB operates when the corresponding breaker fails to trip under feeder fault/bay fault condition. LBB will extend to the trip concerned busbar of that breaker(two main and transfer scheme) and other ends of the line (i.e., opposite end station).
– You will be more clear with protection schemes, showing LBB operated page.


– float dc ammeter shows which current In the battery charger?
– From DIGSI 5 can we communicate Siprotec 4 relay?
– No, But you can install them on single pc

– anyone has drawn for this 11 kv panel siemens?
– I am having two MFM in different panels both having the same voltage and current but KWH is different. Is this possible?
– Check CTR in both
-Checked it is correct, Current may be the same now but it might be different in different timings, so results in different KWh ratings.
– Load in two feeders could not need to be the same all the time. Eventually, results in different kwh ratings.
– One is incomer and one is outgoer. Only- one feeder connected in that bus?
– No. Then how both currents ratings were same
– it is a plant of 30mw where incomer is trf and connected to og line
– That incomer is getting input from 6 5MW sources
– How much is the difference in values in both meters183 and 258
– Is meter calibration done?
-Check PT also
R-Y 115, Y-B 121 B-R 120
– Angles in 7SR relay.
– TCS Protection is not there in the 7SR17 Relay
-How to make logic for TCS in 7SR17 Relay?
– this will work only in the case of DC coil in VCB
– OK, but how to make an equation for that?
– My existing relay is Rho 3
– In the 7SR relay how to make the equation Like logic? How to make TCS Logic in-display evolution software. How many trip coils are in your breaker?
– Two
– Use two equations
– Assign binary input to 74TCS-1 to 4 in the input matrix. Then assign the same in output matrix by virtual input
– Use E1=V1V2, E2=V3V4
– 74TCS is not available in relay
– Which relay?
– 7SR17
– Is it possible to Use TCS if we don’t have 74TCS?

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– SEL 311B Manual Operating Password please Share
– Should be TAIL or OTTER
– Level 1:OTTER. Level 2: TAIL
– In CT, Due to leakage the oil reaches a minimum level. In that case how to refill the oil?
Whether we refill directly from the top of the CT oresle vacuum pulling thereby bottom filling?

– What can someone recommend as a voltage regulator for a 33kv line that experiences voltage fluctuations once there is any loss of any other 33kv feeder all feeding from the same 132kv bus. Meanwhile, the one that experiences the voltage dips is not on the 33kv bus.
– can we communicate the Schneider relay p442 in Micom S1 studio software?
– Can anyone tell me that when I am injecting 63.5in phase to neutral why I am getting voltages in ph to ph
– You are injecting in one phase or two-phase?
– Only phase to neutral. Rph only
– In the Y phase also 31V showing Not injecting in the y phase. If injecting in the R phase, it should not show in the Y and b phase, but it will show in VRY AND VBR.
– Is there a neutral problem?
– Try to ground the other two phases and check
– Check with three-phase injection also

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– during installation of Schneider electric studio and the net frame is not supported on this window
– how can I download the data model package for Schneider
– You have Schneider software?
– You can download it through the data model manager
– server did not respond
– If you need any particular data model, I will check and sent it to you.
– P442 distance protection relay all software version
– I will check in my system, if available I will send, email id?
– Plz check data model if have then plz
– I am connecting two power supplies in series of 48 V but the current of one is 10A and 2 A what will be the resultant
– Current
– Download data models
– Current will be added in series
– Check your email. I sent P442 data models
– yes I received thank you so much. server not respond
– Use Ge Micom S1 Agile
– How to make a Close circuit supervision configuration in 7SR Relay
– earth resistance value without grid must be less than 5 ohms, Is it correct?
– It depends upon the soil, for some soil should be less than 1 ohm
– What’s the meaning of 4 temperature inputs?
– Maybe for RTD connections
– Yeah. For bearings, stator, and rotor.
– What is the application of RTD, Monitoring the temperature.
-Resistance temperature detector. The resistance changes with respect to the temperature.
– Do we need any configuration in the 7SR relay for RTD?
-I haven’t worked on 7sr but RTDs need configuration

– How to test low impedance ref?
– Anybody has a testing format for REM 615 Like overcurrent, earth fault, thermal overload, phase reversal, negative sequence overcurrent protection for the motor, motor load jam protection, and motor start-up supervision?
– The testing procedure of 7SA522 if anyone has please share it? Which relay to set directional
– Does anyone have a SIPROTEC 5 .sim file to share?
– Single-phase pick up and three-phase pickup will be different for overcurrent Protection in relay Or not?
– In relay 7SJ64
– Idmt time at normal setting and 2 times current injection are coming same is this possible
– At a normal setting, the relay will pick up only.
– Check the output trip logic

– Can anyone clarify me LBB scheme 220kV
– Can earthing of CT 2ndry neutral on both sides (at panel side and at field side) can cause this differential current?
– Does anyone has experienced this case?

– That a transformer differential relay tripped even when the breaker is opened? Some differential current flowing when the breaker is opened
– In this case, the current doesn’t flow in the relay coil. it will circulate if both field side and panel side star point earthed
– Check DR
– if transformer trip on diff. relay on through fault what’s the reason?
– Check differential settings and harmonic blocking during energization.
– can we disable the external fault trip in Micom p642 diff?

– after running the generator for 3hrs the turbine guide bearing temperature would rose from 50-62, and if the machine is not shut down it will continue to alarm and trip point.
– Our plant has 6 generators of 96.4mw each, suddenly one of them developed high-temperature issue from the turbine guide bearing. It is a hydropower plant
– Increase the bearing temperature limit up to 85-degree Setpoint
– Won’t that cause bearing burnout as all other generators don’t get up 58 degrees?
– What about the oil temperature in that system?
– If the oil temp is high, too the bearing temp will be high. So you need to inspect cooling systems for turbine oil. The oil temperature also do rise but as usual, it should be lagging and that is what we are getting
– If you are using water in a cooling system, just inspect the water entry. Especially valves which allow cooling water to circulate.
– It’s self-cooling, when the shaft rotates it stir up oil in between the gap between it and the bearing providing lubrication and cooling at the same time
– forbearing to be at low temperature, the oil in its gap must be at a low temperature too. But the oil is cooled by either air or cold water system. So I am advising you to inspect the cold water system or air system. Because this shows that the system that cools oil is not working properly.
– Ok sir, our system is an enclosed type, no water cooling system, and we checked all the breeder points but no issues.
– Ok continue to troubleshoot bro.

– Hello, how to check if fiber optic between two relays is a healthy connection?
– Siprotec 5
– Anybody service provider near Bagalkot Karnataka. Like: TL, T/f, ht Panel relay breaker, cables
– How to make it possible for these two devices to communicate, they are connected using optic duplex LC
– anyone has the 7SJ85 test procedure, please?
– do you mean communicate as a protection interface for line diff 87L?
-Check device id

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– Can anyone tell me how to test low impedance ref Secondary injections or stability?
– Secondary injection
– I am facing a problem with distance signals Configure in the extended system interface
– You will get the signals which you require

– Need to apply 1500V DC voltage for testing. Have anyone came through the 1500V DC voltage injector kit?
– In the 220kV scheme with two main and one transfer bus does the logic inputs of TBC and Bus coupler are fed to that bay relay or not Or using Goose it is done can anyone tell me
– If I am understanding correctly, I would say yes you would get those signals wired to your bay relay as inputs then if needed send it via GOOSE to any other relay that needs it for its logic. Only during maintenance, you shift to transfer bus through 89T…so bus bar protection should not Operate for transfer bus For bay units, only bus isolators status (89A&89B) should be given. It should operate for Bus-A and Bus-B fault.

– For directional earth fault relay uses positive sector negative or zero?
– Generally, we negative and zero sequences not positive sequence

– Relay is showing negative power instead of positive, In this case, the current is lagging voltage, How, it is leading As PF is negative

– In capacitive load current leads voltage, In inductive load, current lags voltage, Current Our is an inductive load
– I guess real power is flowing in the reverse direction. You have to reverse the CT staring, change the PQ direction in Siemens bcu

– if you have calculations for differential relay for transformer 132/33, 132/33/11 Kv, can provide us with my regard

– There is interference between drawing possible to amended and reupload, I’ll try to convert it from my pc Relay is not time synced
– What is the SPS scheme used in the Power station?
– in Micom p442 relay how R1, R2, R3, R4 PP, and PG CALCULATE How-to measure the resistivity of water?
– Trafo is getting tripped at night in transfo differential Even though there is no current at night why it is tripping on differential

– I am testing an MFM em6400, I want to change the power factor From lag to lead
– Using a single-phase is it possible Only positive and negative is changing in inductive
– anybody tells me how set the R1, R2, R3, and R4 P-P and P-G in Micom p442 it’s very urgent
– Which relay?

Can you send fault data? And DR Abb vd4 (vcb medium voltage) technical manual Required Trip, close coil, etc details

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– what is phase over-current, and over current in relays, Can anyone tell me what is Sf in the earthing calculation
– As I referred, it is the diversion factor for which fault is being distributed across the ground network through transmission line ground wires.
– Ratio of Ig/ 3Io. MTA is -15deg, RCA is +- 90, Then angle will be 60-0-240 For earth fault 75 0 255 have anyone use kocos artes kit for test distance protection relay
– How much is the knee point voltage of nct
– Vkp = K * If/CTR * (RCT + RL + RR)
– Vkp is the knee point voltage. K constant taken as 2 If – max. Fault current
– CTR is the CT ratio. Rct CT winding resistance
– RL loop lead resistance in ohms. RR relay burden Or do knee point voltage test
– What mean by 40Rct+400v in ct details?
– <= 40-ohm winding resistance 400v knee point voltage < 30mA at 100 volt while knee point test 21/10/2020, 19:35 –
Greetings house, up till now our problem of guide bearing temperature rise has not been resolved. This sketch is my observation when the generator is operating but I’m not a mechanical engineer.


– Other generators don’t behave this way How to test under Impedance? The setting is 0.02 P. U, Relay is REM545
– how to test Micom p442 distance protection relay as well as setting.
– In the transfer bus how the sequence of operation will be performed
– what is the cause of tripping of incomer due to outgoing feeder trip on high set earth fault.
– How to test pole slip

-For overcurrent protection, On Which side CT low forward power protection and reverse power Protection is generally there?
– Neutral side CT or Phase side CT
– What’s the meaning of the four-step in this protection?
-Four steps mean four different stages, 4 different levels of NPS you can configure.

– Which version of DIGSI is compatible with window 8?
– One problem we are facing is that with stator earth interterm trip is also coming
Wiring checked what may be other problem

– I can’t change the common mode to RSTP Updated the firmware to P14231QB….B60L.
– How to enter in setting mode
– What do you want to do in settings To view setting only And to check measurements?
– Press down arrow, System data will come Then press right now, You will find measurements, configuration, settings
– I found these now But I am not able to enter any option
-If you found measurements, you have to press the down arrow
– Yea but nothing is happening
– You have to reset the trip and alarm, then you try
– Press the book 📖 symbol, It will show all Alarms, then press c.
– I am pressing the book key but nothing is happening
– How come out of this menu
– Press c
– Nothing is happening by pressing the c key also

– Once u can restart and do the same
– You have to switch off the relay, wait for some time then switch on.


– How compensation factor is used in the distance relay?
– When I change the star point then does protection operate or not?
– In the case of non-directional overcurrent, Relay is showing power in negative So I want to change the polarity.
– In directional it will not
– Depending on each direction (reverser or forward ) Starpoint to consider, I have set as forward
– P1 is the bus side and P2 is the line side, With S1 as star point

– When I am shorting the TB for changing the meter the current is still not zero. It is showing as 5A
– Actual load current is 64A, After shorting it is showing as 5A, not 0
– Please Share 7UM6211 Test Report
– Is this a balanced phase or are Y and B interchanged
– Yes the rotation is clockwise, According to me it is an ACB phase sequence. So Y and B needs to be interchanged


– I Am asking if anyone in here knows how to run two generators in parallel and kindly assist with the schematic diagram
-I have two generators

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