Answer / haider imam

vvvf is genaraly use in ac drive because only change
frequancy in ac drive in dc drive there is no any
ferequancy so how regulate this.

Answer / j.kesavan

A THYRISITOR DRIVE ,ITS VARING THE VOLTAGE AND FREEQUANCY
IN AC, DC DRIVES.

Answer / ismail

VVVF MEANS VARIBLE VOLTAGE AND VERIBLE FRIQUENCY IT TAKE DC
VOLTAGE TO RUN DAT VOLTAGE IS MAY BE 24V DC CORRENT ONLY
DEPENDING UPON THE APPLICATION IT IS BASED

How to conduct a Hipot test on a 11KV cable?

2 Answers  

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why we grounding the neutral of a transformer?

3 Answers   GAS,

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How one can check the MAIN of a house wiring ?

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how much kn lightning arrestor is used in 11kv line

8 Answers   Power Grid,

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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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Sir I hv to fix 20 ton ac how much electrical power need apply?

1 Answers   Sealand Restaurant,

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What is function of inverter? and who it's operate & what are controlling devices are used?

2 Answers   Carrier, Dalkia,

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why the voltage level is changed when the unearth cable is earth

2 Answers  

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Where double earthing is required? Is there any power specification to have double earthing?

10 Answers   Delphi,

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What Should be the value of Vector Surge angle at Tripping and how to calculate it?

0 Answers  

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What is Surge arrest? How it work?

4 Answers  

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