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Purpose: The megger tests the integrity of the insulation between conductors that run side by side and do not physically meet or connect. Meggers or Mega-ohm testers also are typically used to test the dielectric in coaxial cable. Meggers are used to test the insulation of buried cables by placing a lead to earth ground and one lead to the outer conductor of a coax cable or any or all conductors of multiple (more than one) buried wires. Method: introduce a high enough voltage to the conductors eventually the current will travel betwen the conductors. Read the indicator to see the amount of resistence to current flow on the meter indicator. the reading will generally be in millions of Ohms (megohms)
MEGGER
Megger is the portable insulation tester. It is used to remove very high resistance of the order of mega ohms.
PRINCIPLE
The instrument works on the principle of ratio-meter/ohmmeter.The required deflection torque is produce by both voltage and current.Due to the interaction between the magnetic field produce by voltage and current,the deflecting torque is produce.The required coil are so positioned that the deflecting torque is proportional to the ratio V/I.
WORKING
Resistance to be measured is connected across the test terminals i.e. connected in series with the deflecting coil and across the generator.When current are supplied to the coils then they have torque in opposite direction.
- If the resistance to be measured is high,no current is flowing through the deflecting coil.The controlling coil will therefore ,set itself perpendicular to the magnetic axis and hence,set the pointer at infinity.
- If the resistance to be measured is small,a high current is flowing through the deflecting coil and the resulting torque sets the pointer to zero.
- For intermediate values of resistances,depending upon the torque production,the pointer is set at a point between zero and infinity.
- The hand driven generator is of permanent magnet type and it is designed to generate from 500V to 2500V.
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What is the importance of Megger test?
Megger tests are important because the test makes sure that your electrical insulation is safe and operating as intended. Megger tests are performed using a Meg-ohmmeter.
What is the number of a megger test to shoot for?
A good number on a megger test should be around 2 megohms.
What is the accepted value for megger of 500 kv Ct tested by 5 KV DC Megger?
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.
How do you measure the earth resistance?
megger
What kind of tests is a megger used for?
A megger is an instrument that generates a high voltage. That high voltage is then used for measuring insulation resistance, especially that of electrical devices.
What mesurement megger?
It is measurement done by megger tool of measurement .
When was Megger Group Limited created?
Megger Group Limited was created in 1889.
What is the output voltage of megger is it ac or DC?
megger are available in ac &dc
What is the voltage used for megger check of aircraft looms?
I did them with a 1,000 volt megger .
What is the population of Megger Group Limited?
Megger Group Limited's population is 1,500.
What is the g in a megger test?
It is the terminal on the megger that the ground cable connect to when testing a device to ground.
What is the importance of Megger test?
Megger tests are important because the test makes sure that your electrical insulation is safe and operating as intended. Megger tests are performed using a Meg-ohmmeter.
What is the number of a megger test to shoot for?
A good number on a megger test should be around 2 megohms.
What is the accepted value for megger of 500 kv Ct tested by 5 KV DC Megger?
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.
Where can Megger testers be purchased online?
Megger testers can be purchased online at the Grainger website. Once on the page, type "Megger" into the search field at the top of the page and press enter to bring up the products.
Why is multimeter not used for insulation testing instead of a megger?
No, you cannot use a multimeter in place of a megger. The megger is used to measure insulation resistance, which could be hundreds of megohms or so. In order to do that, you need a high voltage so as to develop the current needed to sense the resistance. Using an ordinary multimeter would not work as the applied voltage is not high enough, causing the sensed current to be too small to detect.
Can a megger tester cause injury to humans?
A megger device produces hundreds of volts in order to provide resistance values in the order of hundreds to thousands of megohm. The DC volts produced by a megger can and will harm humans.
