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Megger test
On the whole megger testing is non destructive. What happens is a DC voltage is applied to the device or winding under test. It is an insulation test to see is the insulation has been injured in any way to cause a short circuit when normal power is applied to it. On my megger there are 3 ranges 300V, 750V, and 1000 volts. Applying the proper voltage is essential to not damaging the device you are testing. Working voltages up to 240 volts should use the 300 range. Working voltages up to 600 volts use the 750 volt range and working voltages above 600 use the 1000 volt range. As you can see if you used the 1000 volt range on a device that had a working voltage of say 24 volts you could damage the insulation just by testing it. So meggering a device is non destructive if you use the tester as its instructions tell you to.
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Why ac megger not use in cable meggering?
Because the cable has capacitance, and an AC source would not be able to distinguish between capacitance and leakage.
What does it mean by meggering?
On the whole megger testing is non destructive. What happens is a DC voltage is applied to the device or winding under test. It is an insulation test to see is the insulation has been injured in any way to cause a short circuit when normal power is applied to it. On my megger there are 3 ranges 300V, 750V, and 1000 volts. Applying the proper voltage is essential to not damaging the device you are testing. Working voltages up to 240 volts should use the 300 range. Working voltages up to 600 volts use the 750 volt range and working voltages above 600 use the 1000 volt range. As you can see if you used the 1000 volt range on a device that had a working voltage of say 24 volts you could damage the insulation just by testing it. So meggering a device is non destructive if you use the tester as its instructions tell you to.
What is impedance matching?
making impedances identical. when done between supply and load it is done to maximize power transfer. when done on cables and busses it is done to prevent or minimize signal reflections. a low impedance mismatch reflects an inverted signal, a high impedance mismatch reflects an inphase signal.
When checking in a load what must be done with cases that say Mixed on them?
When checking in a load, what must be done with cases that say "Mixed" on them
When checking a load what must be done with cases that say mixed on them?
When checking in a load, what must be done with cases that say "Mixed" on them
How much volt apply to instrument cable meggering?
500v
Why is AC meggering not used?
You do not use AC to megger a device, because the purpose of meggering is to measure the insulation resistance of the device. You use DC to do that. If you used AC, you would be unable to differentiate between insulation leakage and capacitance.
Why MICC cables are meggering?
since the MICC cable the isolation between core is less as well as the outer sheath has probability of getting damaged during installation so meggering is important Any clarification mail to amal_elias@ymail.com
When using a megger at 1000v and your reading is 2700 megohms is it a problem?
What is the acepable rating on a #3 wire when meggering @1000v
Can you use ac supply for cable meggering?
No. The cable has capacitance, and an AC source would not be able to distinguish between capacitance and leakage.
Why ac megger not use in cable meggering?
Because the cable has capacitance, and an AC source would not be able to distinguish between capacitance and leakage.
What are the type of pre commissioning testings done before commissioning a electrical substation of voltage rating 110 kilovolt?
Depending on the equipment required for the substation,some of the tests are as follows: meggering,hi-pot testing,continuity checks,c.t. testing,relay testing,ngr testing, capacitance bridge test's on transformers.
Where can you get on line IEEE standard for 600 volts cable testing?
You can try the IEEE website, but for any good, useful info from them, you have to be a member. Have you tried the NEC (book, or online) for info on 600V cable testing? I would think that a basic "Meggering", and/or "High-Pot" testing of the cable would suffice.
Megger testing is done with DC or AC votage?
Earth testing results should be related to the voltage source, i.e., AC in most situations. AC reacts to resistive and reactive loads, DC to resistive loads only. Not all earth testers, however, use AC.
What is the present perfect tense of do?
have done OR has done I have done you have done (singular) he has done she has done it has done we have done you have done (plural) they have done Examples are: I've done my homework. She has done it. The builders have done the repairs.
It was done before it was done It was done while it was being done And after it was done it was never done at all?
the color purple but not the movie
What is the difference between done and done well?
Done is if you've just done it. But well done is when you did it well.
