We use ungrounded DC system (220V/110V) for control and
protection system in substations etc. Suppose we have long
2 core DC cables running from our DCDB in control room to
the load (length of around 2 to 3 km). Do we need to
protect these long DC cables from earth leakages or not? If
yes how?
Answers were Sorted based on User's Feedback
Answer / krishna
Usage of differential relay for 220V/110V is not an
economical idea. Differential protection is the costlier
protection. DC Cables should be protected from earthleakage
bacause of which voltage differences occurs and trips the
circuits due to large variations. I suggest to go for
MCCB/MCB of required rating which trips the circuit when
earth leakage occurs.
| Is This Answer Correct ? | 5 Yes | 1 No |
Answer / ch.shankar
use dc differential relay or poles insulation monitor which
will help u to measure leakage
| Is This Answer Correct ? | 5 Yes | 3 No |
Answer / k.prakashchandra
Normally dc earth fault locater is employed. If one polarity
shows earth fault there is nothing to panic.Heavy fault
current occurs if the other polarity also develops fault. If
tripping is provided ,the protection may get lost.
| Is This Answer Correct ? | 1 Yes | 0 No |
Answer / sanjay choubey aditya electron
You can use online Insulation Monitor Bender Germany make
products for above requirement you can also see website for
more details: www.bender.org many Steel Plant, Substation
are using Bender products same applicaton.
| Is This Answer Correct ? | 1 Yes | 0 No |
Answer / sanjay
You can use online Insulation Monitor Bender Germany make
products for above requirement you can also see website for
more details: www.bender.org many Steel Plant, Substation
are using Bender products same applicaton.
| Is This Answer Correct ? | 0 Yes | 0 No |
why the secondary winding of the transformer is not open circuited ?
5 Answers Nepal Electricity Authority, Torrent Pharma,
What is pole slipping relay? When it is operated?
Why one can experience electrical Shock due to Voltage or Current?? or both voltage or current??
What are the advantages and disadvantages of negative feed back?
draw the restricted earth fault protection circuit install on power transformer and identify its parameters and draw C/C curve of it
In our domestic single phase line if you don't have a ground connection (earthing)how will you separately use earth in a specific power supply board.
what is linear motor?
What is the funstion of buscoplure in LT panel? which propouse using the buscoplre
Briefly describe your ideal job?
AC current is flowing in a wire in your home how can you measure it(name of the instrument)
which transmission is cheaper ac or dc?
boiler is running in rankine cycle and deisel generator is....?
Civil Engineering (5086)
Mechanical Engineering (4456)
Electrical Engineering (16639)
Electronics Communications (3918)
Chemical Engineering (1095)
Aeronautical Engineering (239)
Bio Engineering (96)
Metallurgy (361)
Industrial Engineering (259)
Instrumentation (3014)
Automobile Engineering (332)
Mechatronics Engineering (97)
Marine Engineering (124)
Power Plant Engineering (172)
Textile Engineering (575)
Production Engineering (25)
Satellite Systems Engineering (106)
Engineering AllOther (1379)