Interested to Buy Any Domain ? << Click Here >> for more details...
what is restircted earth fault relay,how it works? what is
diffrance btwn normal earth falut relay & restricted earth
fault relay?
- 1 Answers
- 5709 Views
- I also Faced
- E-Mail Answers
Answer Posted / javad ahamad
both e/f relays are different. consider an alternator, its
neutral is earthed through a
resistance inorder to limit earth fault current .then we
cant protect the 100% winding from
differential e/f relay only.because if an e/f occurs at
very near to neutral point the driving
current to operate relay will be very small. there for it
cant be sensed by this method,
we can protect up to 80%(approximate value.depent upon
resistance)only.at this situation
we r providing a restrcted e/f relay to protect the
remaining winding ie 20%.this relay
have very low current setting.by the combination of these
two we can protect 100% winding.
| Is This Answer Correct ? | 6 Yes | 0 No |
Post New Answer View All Answers
what is The difference between national electrical code and I.S.Code (electrical) and what is the value of NEC in electrical engineering field
What are the advantages of hydropower?
WHICH SIZE A.B.CABLE IS USED FOR 11KV.
A 7 storey building has a floor area of 35,000sq.ft on each storey. On the ground floor 11KV electrical sub-station is to be erected. A load of 3kw for every 400sq.ft (p.f is 0.8) is proposed for each floor. fire pump 7.5hp, water pump 5hp, lift 2 nos, each 10hp and 20shop load of each shop is 5kw. calculate a. load each floor b. total load of building c. L.T feeders for aech floor and from transformer to main. d. distribution diagram e. capacity of sub-station/capacitor bank f. line diagram
what is vA rating and class of a ct.
what is zinc diffusion?
how to select energy meter? have any calculation?
What are the disadvantages of thermal power plant?
HELLO SIR, IAM PREPARING HPCL EXAMS. SO PLS SEND MATERIAL OF HPCL ELECTRICAL ENG..TO VIJAY_8888@YMAIL.COM
TRAFO 1. WHY BREATHER IS USED. 2. WHY OIL GOES DOWN IN CONSERVATOR TANK. 3. WHY WE ARE TAKING OIL SAMPLE TAKING FROM BOTTOM OF TRANSFORMER. 4. HOW TO CHECK IR VALUE OF TRANSFORMER. 5. WHY OLTC HAVING BUCHHOLZ TRIP ONLY; WHY NO ALARM. 6. OFF LOAD TAP CHANGER OPERATION PROCEDURE. 7. TR. SHUTDOWN / ISOLATION PROCEDURE. 8. WHEN THREE TRS. IN PARALLEL, ONE TR. IS NOT SHARING THE LOAD – WHAT IS REASON AND WHAT YOU WILL DO. 9. WHY TR. HAS OLTC IN HV SIDE. 10. WHAT IS % IMPEDANCE. 11. WHY TR. RATING IN MVA. 12. WHAT IS VECTOR GROUP IN TR. 13. CONDITION FOR PARALLEL OPERATION OF TRS. 14. WHAT IS TERTIARY WINDING. WHERE IT WILL BE. 15. IF TR. TRIP ON BUCHHOLZ OR TAP CHANGER RELAY, WHAT YOU WILL DO. 16. DIFFERENCE BETWEEN OIL TEMP. AND WINDING TEMP. PROTECTION 17. HOW WINDING TEMP. IS MEASURED IN CAST RESIN TR. 18. DIFFERENT TYPES OF FAULTS IN TR. Trafo - Page-1 of 2 19. WHAT HAPPENS WHEN TR. CHARGED FROM LV. 20. WHAT WILL YOU DO IF MEGGER READING SHOWS ZERO BETWEEN LV WINDING AND EARTH. 21. CAN WE INTERCHANGE BUCHHOLZ RELAY OF MAIN TANK AND OLTC TANK. 22. IF THE LINE BETWEEN BREATHER AND CONSERVATOR TANK 23. LOCKED, WHAT WILL HAPPEN DURING LOAD CYCLE. 24. WHAT IS THE FUNCTION OF OIL SEAL IN BREATHER. 25. WHAT ARE LOCATIONS FOR BUCHHOLZ RELAY FIXED IN POWER TR. 26. WHAT ARE CHECKS IN POWER TR. DURING MAINTENANCE. 27. WHAT IS IMPORTANT WHEN WE CHECK OLTC OPERATION DURING MAINTENANCE. Trafo - Page 2 of 2
What is phase cross over frequency?
Why reactors use before incoming of ac vvfd drive?
What is safety of Ht panel
how to test and calculat the head and discharge in borewell compressor
WHY NUTRAL GROUND SYSTEM USED IN 33KV SYSTEM
