Answer / shantanu dash

To protect the HT Motor, Motor protection Relay with the
following protection features are used in HT Breaker. they
are :-
1.Short Circuit
2.Excessive Start time
3.Thermal Overload
4.Locked Rotor during running/start up
5.Unbalance/loss of Phase/single phasing
6.Earth fault
7.Loss of Load
8.Temperature supervision of motor
9.Limitation of No. of Starts/Time between starts

Answer / sivaraman

We have to use for Motor Protection Relay (SPAM 150C)

1.Short Circuit
2.Excessive Start time
3.Thermal Overload
4.Locked Rotor during running/start up
5.Unbalance/loss of Phase/single phasing
6.Earth fault
7.Loss of Load
8.Temperature supervision of motor
9.Limitation of No. of Starts/Time between starts

All above facilities are available in this relay.

if power factor comes in leading & showing -0.95. Is there any effect on electrical system? if yes, then please tell me what would be the effects. & how long we keep power factor in leading. Keeping power factor in leading shows more KW & less KVA is it correct or not.

2 Answers   Jakson,

---

For overhead protection we use which transformer?

0 Answers  

---

how to calculate the starting current of a motor? gopal

3 Answers   JIPT,

---

how can we measure rotor current of a 3phase wound rotor induction motor connected to liquid resistance starter

1 Answers  

---

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

4 Answers   ITC Infotech,

---

---

if generator is running in iso mode parrallel with grid and suddenly grid breaker off what will happen?

6 Answers   century,

---

What is Diff btw Fire Alarm & VESDA System???

0 Answers   EFY, Emerson,

---

what is EIB lighting control system? what is the advantages of this system?

0 Answers  

---

What is stepper motor?

0 Answers  

---

What are the types of excitation system?

0 Answers  

---

How RTCC works with OLTC

1 Answers   Siemens,

---

What is the need for checking knee point voltage for CT's?

1 Answers  

---