Interested to Buy Any Domain ? << Click Here >> for more details...
For Synchronisation of DG Sets Sometimes we people use NIC
(Neutral Isolation Contactor) Instead of 4-pole ACB or any
switchgerar..Please guide me why is it so????
- 4 Answers
- 30395 Views
- Piramal Glass Limited, I also Faced
- E-Mail Answers
Answers were Sorted based on User's Feedback
Answer / srikanth shreenidhi
Whenever DGs are paralled & synchronised one should have a
common neutral.If neutral of one generator fails
automatically the neutral of other dg sets which is on a
common bus takes over.Whereas if the DG has a 4 pole
breaker and neutral fails it will be impossible for the
system to continue as all the dg sets will have a switched
neutral.
Secondly in case of neutral/contactor failure the user will
have to change only the contactor instead of the whole
breaker
However when only one DG set is used we always go with 4
pole breaker.
| Is This Answer Correct ? | 16 Yes | 8 No |
Answer / vinod
when a DG set is started and as dg voltage is building up it is necessary to connect the lowest potential point of generator first with the system which it is to be feed, that is the neutral as first. then the breaker can be closed if the set is required to be parallel first. the reason is the system which the DG is intended to supply may have a neutral potential which can be at a different potential other than the DG. so in order to establish a common neutral NIC is used. if NIC is not there and DG neutral is always solidly connected to the BUS then grounding impedance of the whole system is reduced and in turn fault in system can lead to a higher fault current.
| Is This Answer Correct ? | 9 Yes | 1 No |
Answer / muniraja1283@rediffmail.com
above said subject full very satisfactury
| Is This Answer Correct ? | 3 Yes | 4 No |
Answer / zuber ahamed
Whenever DGs are paralled & synchronised one should have a
common neutral.If neutral of one generator fails
automatically the neutral of other dg sets which is on a
common bus takes over.Whereas if the DG has a 4 pole
breaker and neutral fails it will be impossible for the
system to continue as all the dg sets will have a switched
neutral.
Secondly in case of neutral/contactor failure the user will
have to change only the contactor instead of the whole
breaker
However when only one DG set is used we always go with 4
pole breaker.
| Is This Answer Correct ? | 1 Yes | 5 No |
What is the effect on in Zone and out zone fault if Phase side CT is Vk/2<30 mA and Neutral side is CT is Vk/4<30 mA for Transformer REF protection
why insulation cost is more in underground cable than in overhead line?
what will happen if neutal in AC ckt will get open
When lag/lead/lag-lead compensation is employed?
State four criteria's for selection of site for nuclear power station.
what are the types of cooling systems used in motors?
How to make vector group test of transformer?
how to find transformation ratio of squirrel cage induction motor
What is DC power factor??
when we start the tube light, then it takes initially 1100 volt, after glow it takes 120 volt?(when we give 220 volt a.c.)
how system voltage affect the power factor or vice-versa.
can we use HT cables for LT power supply ?
-
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)
