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Sample group discussion:

– Anybody can guide me about zero-sequence current?
– I have only phase CT and residual connection.
– If no CBCT is available then I0 how I can take it in line.
– What equipment, and Model?
– L&t ACB Breaker and mm10 relay.
– You have required to give the settings of measured earth fault protection in the relay, so by residual connection io directly come into line.

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– Anyone knows how to check the capacitor with a multimeter

– Can anyone helps to identify, in actual what is the main fault is? It occurs from last week
– master and o/c & E/F fault relay trip. And Simultaneously line Side SF6 breaker trip
– We have 9 MVA, two power transformers in 66 kV Switchyard Fault occur only on transformer 1 and only line Side SF6 breaker trip, I don’t understand this? Please help
– O/c & e/f I think backup protection for short circuit or internal faults inside the TR.. check your protection scheme to understand further.
– all I can tell u is, it may be a heavy imbalance in the loading of the line. if it occurs once in a while & goes away please note this & revise your settings through relay coordination.

– Anyone here, who can tell me about solenoids?
– Like this one solenoid
– Our Switchyard SLD, also incase SF6 breaker out of 3 poles 1 pole does not get close (remains open). Kindly check this out.

– On my site, 33kv ht cable IR values are R= 60 megaohm, Y=1 gigaohm, B =1 gigaohm. Please give suggestions if energies the cable.
– How much voltage was injected into the cable?
– 1000 volt

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– Try to inject 5kv. From my experience, If you got the same value you can charge the cable.
– 60 megaohm is acceptable if I injected 5kv.
– If is it possible to keep the cable in sunlight, then conduct IR you can get better value.
– I had charged the 11kv bus when I got cable IR around 10 M ohm.
– Clean the cable jointing kit perfectly, then means if you find any carbon in cable termination. IR value can also improve by doing this.
– Around 1km cable laid
– I Am not saying to clean all the cable. Just clean only the HV Termination kit.

– If it is possible to try to do a route survey also as per standard minimum of 100 megaohms is required?
– Use a blower to heat the termination side it is ht sleeve

– Can anyone tell me the difference between the Hipot test and the IR Test of cables?
– In the Hipot test, we check magnetic earth leakage current. In IR test check cable insulation.

– the procedure in the Hipot test if it’s 11 KV we have to apply 28 kV for 1 minute and measure the leakage current in Milliamps, in IR test we have to use 5 KV DC Megger and measure the resistance in megaohms

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– Why it is 28kv? why can’t we measure with 5kv?
– The Hipot test formula =80% ((2*rated voltage) +1kv)
– In the formula, it’s not coming 28 kV
– For your understanding, I send the Hipot test voltage of switchgear as per standard, for differentiating Hipot and IR Test.

– How to increase normal current from 0.4 to. 08 by ABB REJ501 relay?
– Ct ratio 125/1 amps
Now want to change .4 to.8.

– Hi anybody has an idea how to calculate the THDi from my current measurements Without the use of a Multifunction meter?

– Why impedance correction factor is needed for short circuit analysis
– anybody use line differential relay 7SD8021? Please share the setting details.
– where this relay is used?

– Please I need a Test Report Format for REU615 as a Synchronization Relay

– Anyone can help, this contactor is not on that’s why my motor not on any possibility

– Underground cable testing procedures.
– Check the coil and auxiliary contacts, check control supply and main supply

– I working on a 66/33 kV substation plant trip due to the VT fuse failure alarm. How to troubleshoot VT fuse Failure alarm?
– Please check the relay configuration. VT fuse fail should not go for tripping only for alarm need to be configured.
– Check the fuse may be broken, and I have also faced the same issue.
– Here alarm command parallel-connected master trip relay.
– It should give only a fuse fail alarm, but it should not give tripping signals.
VT fuse failure relay

To join our discussion groups:

– what is the use of short circuit analysis in relay setting calculation of a line or transformer? Why, because line settings are mainly calculated from the line impedance only not on short circuit data & similarly for transformer relay setting also from Transformer MVA & Tap setting are mostly needed.
– What is the contribution of short circuit analysis to distance relay & differential relay settings?
– what will you find when visiting a power station, green building, and Fiber optics factory!

To join, Please send interest on WhatsApp number, click.

Click here to join the Protection Relay Discussion Group on telegram

– What are the Commissioning procedures of HV/EHV types of equipment and different types of tests required before and After Energising the new lines/feeders, Transformers/Reactors?
856: You’re welcome for any request
Rai: Anyone has Siemens Step 7 smart software?

– Can anyone share the Commissioning and maintenance of the electrical power system by Keith Harker?
– what are the disadvantages of VFD?
it reduces the life of other components like cables transformers, etc. conducts harmonic studies as per IEEE 519-2014, and finds out the solutions. if it exceeds the limits prescribed in the standard then go for a filter

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