Answer Posted / will bg

Prove your meter/megger on a known resistance block. You
should remove any star or delta connection/bridges if at all
possible. If your earth/ground reference is not the motor
frame itself (i.e. a conductor in a cable) then first prove
your earth/ground by measuring on ohms the resistance
between your earth test point to various places on the motor
frame. You should get almost 0 ohms. Now measure your
phase resistances and they should always be fairly equal.
Rule of thumb is 10% variance. Remember the bigger the
motor the lower the resistance. Now on 500 volts DC measure
all phases to earth. Now switch megger to 1000V DC and
measure phase to phase resistance.

What Normal(Tangent) towers and Tension(Cut-point) Towers?

6115

---

what is basic difference betmeen normal & flame proof motor??

2096

---

1.why should we connect the measuring instruments in l.v side in short circuit test of a transformer? 2.why the power factor is less in open circuit test of a transformer?

2012

---

what is mean by transition resistance of transformer?

4476

---

Is it true that in the 3 phase transformer, the limbs of the core are at 45 dgrees to each other. if true, why?

1994

---

what is the difference between ups & inverter

6897

---

Draw a SLD of HT distribution EB grid up to users Transformer?

6145

---

If o/p power is doubled by how much does the sound increase

1030

---

How does a tertiary winding filter harmonic(espcially 3rd one) from entering into load system?

1749

---

What are the operation carried out in thermal power station?

999

---

WHY IS THE EARTH FAULT CURRENT ALWAYS LESS THAN THE NORMAL CURRENT??

2173

---

Differentiate between ideal and non ideal current sources?

1100

---

oil cooled transformer

2167

---

whate is the meaning of balance/unbalance,in stabilizers type

2089

---

how do i work out the Amps of a incommer if i am running 1 37 KW motor and a 0,75 KW motor and some solinoids

1844

---