What is the function of a megger meter?
On the whole megger testing is a non destructive test. 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.
There are two types of meggers, electronic and mechanical. Both can be tested the same way to see if there are operational. Take the test leads and short them together and operate the megger the way you would on a test. The megger meter face should read zero because there is no resistance. Do the same thing again but leave the leads open, this time the meter face should read infinity or no reading at…
How voltage increase in megger meter from 9vots battery to 500 voltage and hw voltage increase in multimeter.?
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.
First you would disconnect the HO bushing connection from ground. Then you would megger low-side phase to ground.. Next you would megger high-side phase to ground.. Lastly megger high-side to low-side phase to phase. You would not megger phase to phase on each side because this is a direct connection.
The megohm meter (or megger) passes the 500, 750, 1000 volts to the wire that needs to be checked. According to ohms law R=V/I, the current in the returned voltage is measured and divided by the resistance (inside the meter). So when the current is high (i.e not properly insulated or leaking), the resistance value will drop otherwise resistance will be high.
There are different types of megger, which is simply a trade name for a range of different instruments. Not all meggers use d.c., for example, an earth-resistance megger uses a.c. On the other hand, an insulation-resistance megger uses d.c. because it applies a constant test voltage across the insulation being tested.
The time duration for a megger test is as long as it takes to turn the handle of the megger about five times. Voltage is generated on the first turn and if there is an insulation breakdown on the device being tested it will show instantaneously. If the megger is an electronic megger hold the generate button down for about three seconds.
A 'Megger' tester is used for testing insulation. It supplies a high voltage and sees how much will leak across from one conductor to another. Old machines used a crank handle to produce the high voltage. New machines use a battery and in inverter. The basic test is betwen the live (hot) wire and earth. Connect one lead to live and the other to a suitable earth point. Crank the handle or push the test…
If the service is connected you can not megger the service ahead of the main breaker. If the service is waiting for connection all you can do is megger between the wires. As the underground service is installed in PVC conduit, no ground circuit will be available between the underground conductors and the PVC conduit. Connect the black lead to the neutral bar in the meter base. Connect the other lead to the L1 lead…