What is Grounding? any difference b\w earthing? if yes plz explan??

3 Answers   ABB,

---

why anti pumping relay is not given to tripping coil of the breaker? why only to closing coil?

2 Answers   INEL, Siemens,

---

7- What is the Dissipation Factor and the difference between it and Insulation Resistance Test? 8- What is the task (function) of DC and AC reactors in power plant? 9- What is the task (function) of (open delta with earthed) in some types in transformers? 10- What is the base of the selection of the vector group in transformers? 11- What is the zig-zag transformer and its function by drawing in large detail? 12- What is the polarity ? 13- Why we make short between phase(R) in high side and phase (r) in low side in vector group test? Where High Side ( R ,S and T ) and Low Side ( r ,s and t ). 14- What are the time on delay and time off delay? 15- What is the vector group? 15- What is the task (function) of different types of vector group such as Dyn11 , Dd0 , YNd1,……..,?

0 Answers  

---

why transformer is conneted to dc for polarity test.it doesnt work in dc?

1 Answers   ABB, KVPY,

---

How can we calculate the rating of capacitor bank to be connected for a particular load(ex.100kw)to improve the power factor from 0.8 to 0.9?

4 Answers   Voltas,

---

---

Working of microwave oven?

0 Answers   LG,

---

What are the three major categories of error?

0 Answers  

---

why CERAMIC material is used in insulators??

1 Answers  

---

why do transformer humm ??????????

2 Answers  

---

what is the difference b/w KVA and KW? the transformer are mentioned KVA rating and the loads are mentioned KW.why?

2 Answers  

---

what is inverter and converter

0 Answers   Hindustan Syringes and Medical Devices,

---

following are the questions asked in interviews: 1) Considering the short circuit fault, which switchgear is preferable, SFU OR MCCB? Which operates faster? whicg one is popular in Indian Market and why? 2)Define SCPD. What is type2 coodination? 3)Why the contactor rating is higher for the fuseless selection than for fuse selection? whether the ratinf of SFU or MCCB remains the same in both the cases? 4)If the HP rating is known then can you calculate the ratings of L.V Switchgear(SFU/MCCB, contactor, OLR) without using the selection chart?

0 Answers  

---