When we use air circuit breaker, it has O/L protection ,time delay SC protection, Instataneous SC protection & ground fault protection. They all have some setting range. But what is the suitable/allowable setting for the above protection which will be safe for the equipment? For example-O/L protection setting have a range of (0.4,0.45,0.5,0.55,0.6,0.65,0.7,0.8,0.9,1.0)xIn Time delay SC protection have a range of (1.25,1.5,2,3,4,6,8,10,12)xIn Time delay setting is 0.02,0.1,0.2,0.3,0.4 Instataneous setting is fixed to 20xIn Gound fault setting is given 100A,300A,600A,900A,1200A This setting are for 2500A ACB. So what will be the basic allowable setting for the above protection? is there any formulae to calculate this<

0 Answers   Lupin,

---

explain how hunting can be reduced in an alternators?

3 Answers  

---

for 1000kva transformer how kvar rating is need for this PFI plant. and how does it will calculate? and Apmpere rating of main cable connection?

6 Answers   Engineers India, GCC, KP, QPSL, Siemens,

---

We have two 1 phase heating coils having same resistance of 25ohm, but during operation one takes 3A and other 6A Is it posiible Pls. explain

5 Answers   Bhel,

---

which type of amplifiers are used in multimete?

0 Answers   NTPC,

---

Re: can you give main difference between ELCB 2pole And RCCB 2pole? And how this devices operated?

4 Answers  

---

what is the back ground of transformer working? applying voltage to primary and emf inducing in primary and secondary? how it is possible? please answer me with scientific approach?

5 Answers  

---

The neutral&earth voltage is 0v.But we were connected the lighting load at the time ballast was failed.why?

1 Answers  

---

What is the difference between UPS & inverter ? which UPS is better and whos got the edge ? what is the difference between & inverter ? which UPS is better and whos got the edge 12 V , 24 V , 36 V etc what are the advantages of 12 V, 24 V , 36 V etc and what are the disadvantages of 12 V, 24 V, 36 V etc thanks

0 Answers  

---

what is first ground fault & second ground fault. This is used in rotor protection of alternator.

1 Answers  

---

WHY THE FREQUENCY IS 50 HZ IN INDIA.CAN WE USE SOME OTHER FREQUENCY.IF SO WHAT IS THE RANGE AND WHAT WILL BE THE EFFECT IN PRESENT POWER SYSTEM IF WE CHANGE THE FREQUENCY AS YOU SUGGEST ?

32 Answers   L&T, MCL,

---

IF DISTANCE IS 100METERS B/W AMP.METER AND CURRENT TRANSFORMER WHAT WILL BE AFFECT IN ACCURACY .METER CAN SHOWING ACCURATE CURRENT OR NOT IF NOT WHAT CAN I DO TO GET 100% ACCURACY.

0 Answers  

---