Answer / fairos

First, for thermal overload relay has no meaning in term of setting it while on running or starting. It purely based on rated current of the motor.

when you look at the nameplate of the motor there should be a data that mention "duty" which normally either 1, 1.1 or 1.2 in value. If the duty is 1 then you can only set the overload relay at 100% of the rated current. If duty is 1.1 then the motor is allowed to operated at 10% higher than it rated current hence you can set your relay at 110% of rated.

Generally people would set at 10-15% higher than rated current. But sometimes being conservative is okay, which you can set the relay below the rated current. This can be done as long as it is not tripping unnecessarily.

Answer / vilas

First take a current of each phase with tong tester,while
running on normal load,
Then set the over load accordding to the load slightly
higer than normal running current, care should be taken
that it should not be more than rated current which is
always mentioned on the motor name-plate.

Answer / pankaj sharma

Set the relay to motor full load current as mention on motor plate

Answer / mohit

set thermal overal relay to 95% of full load current of
motor.

Difference between transmission line and cable?when ever a large water channel has to crossed it is easier to use cable then transmission line why?

1 Answers  

---

In Slip ring Induction Motor we use Liquid Rotor Starter for Starter Every Time Liquid Filling we need add Soda Sodium Carbonate or only Distilled water is Enough.

2 Answers  

---

Why do we give DC excitation to AC Synchronous motor??

9 Answers   Lance, MBM, Polycab,

---

Difference between field rheostat and armature rheostat.

0 Answers  

---

i am completed in B.E(Electrical and Electronics Engineering) with 8 months experience in Quality Control Engineer at Bharathi Industries,Coimbatore.

0 Answers  

---

---

WE HAVE A PROBLEM THAT THE MAIN DRIVE OF OUR CEMENT MILL HAS AN EARTHING PROBLEM?TWO OF STATOR WINDINGS INSULATION HAS BEEN COLLAPSED DUE TO AGING PROBLEM.THE PHASES HAVE BEEN BYPASSED AND NOW THE LOAD HAS BEEN INCREASED.WE CAN'T REPLACE THE MOTOR.KINDLY HELP ME BY GIVING SUGGESTION THAT HOW TO MAINTAIN THE STARTING TORQUE AND CURRENT FOR HIGH LOADS.

1 Answers   ACC,

---

What are the reasons for AVR failure in LT DGsets ?

2 Answers  

---

Why the cores of large transformers build up of circular cross section?

0 Answers  

---

what is the operation of Control Module(CM),MONITOR Module(MM), MONITOR Module DUAL (MM2),Signal Module(SM),Isolator Module(IM), please some one reply me.. the operation and application of these in FIRE ALARM SYSTEMS...

1 Answers  

---

CAN 50Hz transformer work at 60 Hz power supply? if yes how it is possible?

2 Answers  

---

How to calculate the sag on transmission Lines.

0 Answers  

---

line vltage of three phase distribution transformer is 433v and phase voltage is 250v,but we required 230v for domestic distribution,then how we reduce phase voltage of transformer

5 Answers  

---