0
What is the accepted value for megger of 500 kv Ct tested by 5 KV DC Megger?
Wiki User
∙ 14y ago
The value of insulation resistance varies according to the type of CT and manufacturer. It is best to check with the manufacturer for acceptable values. The word 'Megger' is a registered trademark of Megger Limited. Megger Limited's product range includes insulation testers, relay testers, battery testers and many other electrical test and measurement products. Tony Wills, Applications Engineer, Megger Ltd.
Wiki User
∙ 14y ago
Add your answer:
Earn +20 pts
How do you measure electrical insulation resistance value?
By Megger testing (meggering) of the motor any one can measure the IR of the motor. MEGGER is a device used to measure IR. Analog Megger device may generate 500 volts..it gives coil to coil or coil to body IR value...it should not be less than 2 Mega ohm, generally it should be or kept more than 5 mega ohm...thanks ...DEEPAK RAJPUT
What should be the minimum insulation value of a 20 kw 415v phase motor?
415V commonly available wire is 300V or 600V so that would need to be 600V wire to use a megger or a hipot tester (2* operating voltage +1000V) 2000 volt megger or hipot should verify the wiring in this instance 2500v megger will be necessary for 600V wire and wiring devices you also must look and ambient temperature and humidity a test after some operation time can verify this
What is the value of fail megger test result?
Engineers request that 5 meg ohm is the bottom limit. I use 1 meg as a bottom limit when megging conductors before they are energized. I have run motors as low as .5 meg, when the moisture is driven out by the heat of the motors operation the motors usually climbs up to about 2 meg ohms.
What is the acceptable pi value in insulation resistance?
The PI value depends on the type of equipment being tested and the voltage level. Roughly it shall not be below the value of 2.0
What meter is used to bench test a motor for a short or an open winding?
An Ohmmeter or the ohms function on a typical multimeter would be used to bench test a motor for a short or an open winding. First, be absolutely certain that the motor under test is disconnected from any mains. Using a low ohms scale, x1 or x10, one would expect to see some resistance across the motor. The resistance can be quite low depending on the size of the motor, but should not be zero. If it is a motor that has brushes and a commutator, rotate the shaft, with the meter connected, through a full revolution. This rotation could help identify a single defective winding in the rotor. To check the stator, remove one of the brushes so that the measurement current only passes through those windings. Of course, it would help if you have a known good motor of the same kind so that you can compare the readings.
What is the required resistance in mega ohm when performing megger?
Normally the megger should be selected based on the following criteria. 1.Voltage rating of the megger 2.Range of the megger value 3.Manual - Hand operated analogue type 4.Auto- Digital Megger To measure the insualtion resistance of Motor (LV Motors) Up to 500 V/1000 V Megger is sufficient To measure the insualtion resistance of Motor (HV Motors) Up to 5000 V can be choosen Normaly the range starts from 0.5 to Infinity meg value in the analogue However in digital the based on the least count /range of the instrument we can able to measure the insualtion value.
What value of tester is to be used for measuring insulation resistance of three phase 600V cables?
The typical test equipment for this is a megger. The megger is connected to two conductors at a time to test the insulation between the two.
How accurate are the readings of a megger test?
While using megger we only have to see whether resistance breaksdown at the upper value mentioned. Since megger generates high voltage we can check whether breakdown takes place or not.Megger has a range from o to infinity.So it is not possible to find accurate resistance,hence it is used as an insulation tester
What result should you obtain when you do megger tests for motor?
we will get its insulation resistance value wchich should be greater than 200Mohms
How do you measure electrical insulation resistance value?
By Megger testing (meggering) of the motor any one can measure the IR of the motor. MEGGER is a device used to measure IR. Analog Megger device may generate 500 volts..it gives coil to coil or coil to body IR value...it should not be less than 2 Mega ohm, generally it should be or kept more than 5 mega ohm...thanks ...DEEPAK RAJPUT
What should be the minimum insulation value of a 20 kw 415v phase motor?
415V commonly available wire is 300V or 600V so that would need to be 600V wire to use a megger or a hipot tester (2* operating voltage +1000V) 2000 volt megger or hipot should verify the wiring in this instance 2500v megger will be necessary for 600V wire and wiring devices you also must look and ambient temperature and humidity a test after some operation time can verify this
Do you have Megger testing procedures and measurement limits for power cables at 600V rating 250mm plus 50mm THHN?
For 600V insulation Megger NETA & IEEE recommends: Test voltage = 1000V Test Duration = 1 minute Test Value = 100 Megohm minimum (corrected to 20 degrees C) Typically you megger conductor to conductor and conductor to ground. Most will not megger for the full minute and it is up to your discretion. Just watch that the resistance continually increases during the test period. If it is decreasing then you should hold the full minute and investigate the reason. For multiple conductor cables then twist all of the conductors together and pull out one at a time and megger it to the bundle. This will expedite thetesting into as few as tests possible while still thoroughly checking the cable. Note that test voltage and values are based strictly on the insulation rating and the conductor size is pretty much irrelevent.
What does a megohmeter or megger test?
It checks resistance from a circuit or an electrical component to earth, to make sure it is electrically isolated. This must be a very high value of resistance, hence 'megohms'.
How do you use megger tester?
Megger testOn 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.
Can you use megger as a generator?
In effect a hand crank megger is a generator. It generates a DC voltage that is used to test insulation conditions, by applying a higher that normal insulation value voltage to the material under test. +++ My apologies if my addition has already been published, for it's by no means clear what Answers actually does with amendments - as far as I can see here it rejected my first attempt which was more-or-less as follows: Yes, a 'Megger' (actually its trade-mark) contains a d.c. generator but I would not recommend using it as such, for it's designed to create a high voltage at very low current, so trying to use it as a power source may simply ruin it.
What is a tested value in science?
A value accepted by scientists after many experiments and tests.
Megger value for single conductor?
It depends on the value of voltage being applied to the wire in normal use. Voltages up to 750 volts can be used on wires reading as low as .5 meg ohms. Engineers like to see 5 meg ohms on conductor readings.
