what is the main use of ac and dc drives ? it is only used for speed variation or for power saver also?

1 Answers  

---

Work done in a free expansion process is

0 Answers   Caterpillar,

---

Why we are designed only 11Kv and 6.6Kv Alternators, not 33Kv Alternators and Power Transmission side we are designed only 220kv, 120kv, 66kv, 33kv, 11kv, and 440volts, not 20kv, 50kv, 100kv.

2 Answers  

---

why capacitor burst?

2 Answers  

---

why we are using R,Y,B colours for 3 Phase ?

4 Answers   ITC Infotech,

---

How to check the cable fault / hv test of transformer cable.

0 Answers   KSEB, L&T, Siemens,

---

why the vfd motor take current high in vfd panel then mcc panel.current in vfd panel=160A in 93%.and mcc panel it shows 130A. (132kw motor)

1 Answers  

---

What is the difference between Welding Transformer and Normal Transformer?.

2 Answers   DAE,

---

CALCULATE THE TOTAL VOLTAGE DROP AND SELECT THE CABLE SIZE IN MM-SQARE FOR A PANEL-262KW AT 110 METER FROM THE SOURCE SUPPLY , SUPPLY VOLTAGE 240/415

0 Answers   DEWA, Growth,

---

Hi, I've just got into my electrical engineering course and I need some help with a question of mine here. During a site visit, we were shown a main LT panel which has switchgears, ammeters and different kinds of relays and the distribution network from that panel. In the main LT panel I've noted down the current readings as Ir - 163A, Iy - 150A and Ib - 147A. The Line to Line voltage is 415 V at 50 Hz and Line to Neutral voltage is 230V at 50 Hz. From the above details, how would I calculate the kVA rating of transformer? The primary side voltage of the transformer is 11 kV and the secondary side voltage is 415V and the frequency is 50 Hz.

2 Answers  

---

What is meant by impedance? difference between high & low impedance ?

0 Answers  

---

Rated moter voltage and frequency is 380volt 60 hz but moter is running at 380votac 50hz is this harmful for moter winding

1 Answers   Infosys,

---