Answer / ranjan sannyasi

Many of test over an 3 phase transformer you can done, you
have to mentioned about megger test,so that test what actual
done,it's ur qsn...may i r8?
so, It's actually IR test means Insulation Resistance(IR)
test,how much insulated the transformer winding in between
their winding(primary & secondary).You could be known by
meggar test.
1.1st You have to do the PHASE TO EARTH test,how to do the
test? megger have two terminal,one of them you have to
connect with 1st phase (R-phase) or whatever(it may be
another two Y or B),must be one by one,it ds'nt matter ok,&
another with transformer body,its the earthing path.
regarding this test obtaining three of value must be
100,it's must be noted that 100 value is the accurate,if any
of value is 0 then some where in b/w winding & body it may
be leakage,for that DC current** is flowing through the
winding to earth.

2. 2nd test is the vital one.It's PHASE to PHASE TEST.It's
done by like that, suppose megger one terminal is connect R
phase and another one done by Y phase, so like that 1st R-Y,
2nd Y-B & last B-R, same you have find 3 value,like above
those.If all the value are 100 then its insulation b/w
winding are accurate,there have no insulation fault.

Answer / k.prakashchandra

With all the connections removed 1.Primary to body 2. Sec to
body 3.Between Pr and Sec .Find PI value also

can anyone tell me the website for star-delta control diagram?

1 Answers  

---

What are the types of bus duct?

1 Answers  

---

What is GIS (Gas Insulated Switchgear)

3 Answers   Power Grid,

---

If age of Raju is 20% less than Sanju,then age of Sanju is how many % more than Raju

2 Answers   Tech Mahindra,

---

Will it be OK to connect a 5MVA 33/6.6kV Ynd11 Transformer to a Star connected Motor. Or on other words connecting a Delta to a Star. I have another 30MVA 33/11 Dyn11 and would it be practical to convert it to Dd0 consequently converting the Voltage Ratio to 33/6.35kV Dd0.

1 Answers  

---

i have ht transformer of 142 kva with air cooled facility,having secondary voltage 7850volt, and secondary connected full way bridge rectifier .i faced the problem repeatedly that transformer one coil and rectifier diode of two phase was burnt two times. i checked all the secondary ckt. no any short ckt found,then what will be the cause side

2 Answers   Modern Terry Towels,

---

What are the voltage values for LT,HT,EHT and other voltages??

22 Answers   INEL, MNC,

---

what is exiter winding,stator winding,avr?how it will work?

1 Answers   Siemens,

---

i want to learn control schedule for 11kv panel? can any one send the detailed control schedule?

0 Answers  

---

Isolation transformer primary to sec turns ratio?

2 Answers  

---

what r the checklist while installing a 380 kva DG set

0 Answers   Pepsi,

---

if any body have question paper of railway (section engineering),then plz send me .i will thank of him/her.

0 Answers  

---