Answer / denzel101

Calculate the maximum current you want to measure from your
system. for example calculate the full load current of a
supply transformer. if the full load current is 200 Amps
and your meters have 1amp rating, choose the ratio of 200:1
CT.

Answer / pillay

There is no formula for this you just choose the correct size from what is available.
usually size the ammeter the size of the circuit.example the circuit breaker is 200 amps than the ammeter would be 200amps.The CT would be 200:5 or 200:1 whatever is available so long the ammeter is also of the same rating.

why it is important to earth neutral of 3 phase transformer?

9 Answers   IBM, ITC Indian Tobacco Company, RRB, UDS,

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In our plant we have installed new MCC with ELR and CBCT which is detecting some leakage current in the system but it leading to some confusion when to check that in which feeder which is drawing current we put off the whole panel itself but still CBCT detecting some leakage current so can anybody ans me , where i am going wrong or how to detect whether its actual leakage or CBCT malfunctioning.

0 Answers   Saint Gobain,

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what is settable hystersis protection? If any body knows plz kindly post the answer..

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1.what is bus cuplour and main funtions. 2.what is main function of alternator. 3.how many types of dg oils.

11 Answers   Bhel,

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how to meas-our losses for L.T & H.T

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Hi all, please could anybody give me a suggestion about Electrical designs and calculations .. what text book should i follow as i am a trainee engineer and here work going not so favorable to me so please help me friends .. A small discription about my work which is going here is all about Electrical designs like cable sizing, lighting, lightning, Gensets sizing, motor sizing, transformer sizing, generator sizing, circuit breakers, PDB MCC PCC SLDB MLDB panels, Single line diagrams mainly, substation desings, cable routing and layouts, reactive power compensations, power factor improvement, voltage drop calculations, power generations, power transmission, power distributions all calculations i need .. please please if anybody experienced with this problem and got a solution then please help me .. just i need an apt text book for these all calculations and designs ..

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why in a swquence network representation, the negetive sequence generated voltage is taken as zero?

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How to PLC give the command to electrical

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why we use 25 kv in railway .not 11kv, or 33 kv

2 Answers   ISRO,

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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

0 Answers   KSEB,

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why we use end termination kit for ht xlpe cables

1 Answers  

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What is sunrise meeting ?

1 Answers   KSEB,

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