Answer / erharisheee51

i Guess Megger test means Insulation Resistance test ..using
Megger test itself we can able to find the insulation
strength interms of resistance only ..
so what is that question ? please be clear that resistance
and megger test are similar ..

and remaining inductance test i don't know that ..

is it correct , Please clarify

Answer / ramesh

Insulation test for checking of winding healthy condition,
If any short circuit inside area, the motor cannot operate.
So that before energised motor, insulation test to be done.

Answer / stan grzegorski

Megger (or Insulation) test will test ISULATION ONLY . A "
Megger" is one manufacturer of insulation testers . This (&
most other) insulation tester also has a low resistance
range for measuring & COMPARING motot winding
resistance .Insulation resistance is normally measured at
twice the RMS line voltage minimum , (For 240 Volt rated
equipment the 500V setting is used )DO NOT USE IT IF THERE
ARE SESITIVE ELECTRONIC COMPONENTS IN CIRCUIT . ( You WILL
destroy them ). BE VERY AWARE !! The 500 V & 1000V settings
on these instruments is not what they are measuring ,IT'S
WHAT THEY ARE SUPPLYING , & IF YOU ARE PART OF THE CIRCUIT
THAT IS WHAT YOU WILL BE SUPPLIED WITH !The output current
is limited to a safe level , but if there are any
capacitors in the circuit , THIS CAN BE MULTIPLIED MANY
TIMES to a dangerous level.Specifications for insulation
resistance to earth ( Ground /Chassis ), is 1 M ohm ( 1 Meg
ohm , 1,000,000 ohm ), but in reality if isulation
resistance is 10 Mohm or under , the equipment may need
drying out , or is on its way to the bin . The low
resitance range is for measuring continuity , in this case
that the motor windings aren't broken , normally in the
order of a few ohms , & on larger motors less than 0.5
ohms .Inductance is an electromagnetic parameter which
affects AC or varying DC current & is dependent on the
frequency of the AC current or the RATE OF CHANGE of DC
current . ( Higher frequency = Higher inductance ) > In
most AC machines (Motors , transformers etc.)the Inductive
reactance is cosiderably larger than the resistance , &
measuring inductance can identify faults which would be
practically impossible using resistance measurements .

Answer / amit

My senior while
checkin ht
motor ,first he
measured
resistance using
micro ohmmeter
and he got 25m
ohms after tat he
meggered it
getting 5Gohms...
So i asked this
question...

Find active & Reactive Power transmitted in a transmisston line having Vs30 degree(sending end) to Vr(zero degree)at receving end with line inductance X ohm. Vs(30degree)-------------------Vr(zero degree) X ohm

3 Answers  

---

why did the BDV test in transformer?

2 Answers   Jindal Steel and Power,

---

How we calculate the size of H.T cable for any transformer & rating of busbar for any L.T. panel?

3 Answers  

---

why generaters need four earthings

5 Answers   Sasken,

---

how to make neutral to ground voltage less than 5v? my house is under the high voltage transmission line so,proper grounding using rod salt n coal doesnt help me..so wat i do as i cant operate my computer ..this high voltage cause great problem to the motherboard i already two times replaced it.in my house voltage is coming near to 25 v between ground and neutral.plz kindly post ur answer to my email id manish77777@gmail.com ..

3 Answers  

---

Why the stator is rotated in ceiling fans not Rator?

3 Answers  

---

AT THE TIME OF INSTALLING THE POWER PLANT POWER IS TAKEN FROM NEARBY GRID AND GIVING THE SUPPLY TO THE GENERATOR WHICH ACTS AS MOTOR. WHAT IS THE NEED OF RUNNING THE GENERATOR AS MOTOR?

6 Answers  

---

The knee point of a current transformer is normally unique and known.So why in the nameplate of a CT they put the minimum value like this Vk> 400v.

0 Answers  

---

how to read AWG n how to convert AWG reading into mm?

1 Answers  

---

Why the ratation of fan is anticlockwise all over the world?

2 Answers   GNFC,

---

The Source internal resitanse Rs , When equal to Load resistance RL, the maximum transfered is of _____ % of input power?

2 Answers  

---

What is the difference between surge arrestor and surge capacitor?

2 Answers   Shreem Electric Ltd,

---