Failure to do so could result in damage to equipment and electrical shock. The insulation resistance tester resembles a conventional ohmmeter. Megohmmeter definition megger working principle megger working principle megohmmeter circuit diagram the megohmmeter or megger is an instrument for measuring very high resistances, such as the insulation resistance of electrical cables. All persons performing or assisting in the tests must employ all safety precautions to prevent electrical shock to themselves and to others. Megohmmeter teraohmmeter a megohmmeter is an instrument that uses a high value dc voltage to measure the resistance of insulators. The megger company registered the name megger in may 1903 and today offers a wide variety of ir testers. A handy test lock feature and a data hold function are also included. The insulation found on wires, cable, and motor windings serve to protect the wire and keep it separate from other wires. Test interphase resistance by disconnecting the leads from each terminal. Bd loops bdmegger instructions were on the installers side. Using the megger to test a threephase motor is rather easy, though the safety hazards for this procedure are quite high. How to meg a motor with a megohmeter checking motor condition. Typically these measurements are made on electrical wires and motor windings to test the insulation value of the wires.
Some units may also incorporate a hand generator to produce high voltage levels. Accidental touching of two conducting wires can result in an. This professional meter, with proper care, will provide years of reliable service. Megohmmeter making measurements selecting a ramp or steadystate test the ramptest function is an automated test that checks insulation for a breakdown. Megohmmeter 1210n 1250n english user manual v 500v 1kv x 10 300 0 100 2 0 0 400 500 600 20 15 30 40 50 10 0 2 5 50 2 0 10 5 4 3 1. The megger insulation tester is a small, portable instrument that gives you a direct reading of insulation resistance in ohms or megohms. Routinely using a megohmmeter to check insulation in both new installations and as part of a maintenance program is a prudent way to ensure your circuits are safe. During a ramp test, the output voltage starts at 0 v and increases linearly 100 vs until it reaches the specified test voltage or until a sudden drop in measured resistance is detected. This is to be done in a manner as described in this operators manual.
It works by using 2 probes to send a current through the circuit and measuring how much resistance, in ohms, that current encounters. A megger is a highrange ohmmeter, typically used to measure the resistance of wire insulation. Circuit is designed as a lowpower, high efficiency type, using 6f22 battery, 500v range measuring 1. W warning a repetitive beep and the flashing high voltage symbol y. How to use a megger to identify a faulty component youtube. Oct 02, 2015 an insulation tester like a megger can show a component failing that a normal multimeter would not show. Get highquality megohmmeters at grainger to help measure electrical resistances of insulators such as cable jackets, electrical wires and motor windings. The 5 and 15 kv megohmmeters are highvoltage, lineoperated instruments.
Insulation resistance measurements megohmmeter tests warning. So for your safety, here are some tips on how to use a megohmmeter, whether yours is bat. Oct 19, 2015 how to meg a motor with a megohmeter checking motor condition. The value is expressed in megohm 1 megohm 1,000,000 ohms. The fluke 1587 fc is fluke connectenabled so you can download the free fluke connect measurements app to your smartphone and gain. Two nos of wire leads for connecting megger with electrical external system to be tested. This lesson describes safety issues to consider when using a megohmmeter, how to select the correct megger for the job, setup, and the steps necessary to take a megger reading. Users manual test equipment depot 99 washington street. An ohmmeter is an electronic device that measures resistance in an electronic component or circuit.
Megger guide to electrical insulation testing pdf instrumart. Congratulations on your purchase of extechs insulation testermegohmmeter. Megohmmeter using the meter to measure insulation resistance, do the following. Others are designed to accept an input from a high. Voltages of up to 1090 vdc maybe present at measurement terminals of the 1864 megohmmeter and voltages of up to 500 vdc on the measurement terminals of the 1863 megohmmeter. Like any other electrical tool, a meghom is dangerous if not used properly. When servicing, use only specified replacement parts. The test leads must be replaced before using the meter. An insulation tester like a megger can show a component failing that a normal multimeter would not show. The comprehensive product users manual for the amprobe amb4d megohmmeter keywords. In lo ohms mode, the meter turns off after 5 minutes of non use. Timed insulation resistance test model 5882 only 1. Shop here for batteryoperated, handcranked and lineoperated insulation testers.
This is important, because the highvoltage current in threephase systems is far more lethal than a mere lowvoltage shock received in residential setting. To turn the meter back on, turn the rotary switch to. Measurements described in this manual refer to the esd association standards s4. Also called megger, megohmmeter is an electrical tool used for measuring high insulation resistance in electrical items. Megohmmeter working principle megger working principle. Choose from a wide range of specifications to help find the test instruments that can meet your needs. Switches use to select electrical parameters ranges. Crank the handle for about a minute, and notice the resistance reading. This range is suitable for leakageresistance measurements of most types of insulation used in electrical machinery, electronic devices and components, etc. The model 380260 provides three test ranges plus continuity and acdc voltage measurement.
The first step in using an ohmmeter is setting it up. How to test a threephase motor with a megger hunker. Timeresistance testing method this method is fairly independent of temperature and often. The prefix meg describes a numerical value of 1,000,000. To accomplish this with some degree of accuracy, you have to apply at least 500 volts. Troubleshooting with insulation resistance test instruments. We want to prevent installers from accidently replacing good loops by making such a small mistake while testing. Understanding insulation resistance testing pdf 0712 technical assistance 800 34391.
The use of leads or other accessories of a lower voltage rating or category limits the use. How to use a megger to measure and test motor insulation. Using the megohmmeter this is the second lesson in the ammeters, meggers, and wheatstone bridge course. Place one megger probe to the any mounting bolt on the breaker box to test for grounding continuity, then touch the other probe to a motor terminal. They utilize relatively high voltage upwards of vdc to measure resistance. Intended use the 3m model 701 megohmmeter is designed to measure the resistance of static control work surfaces and flooring. Apr 08, 2020 an ohmmeter is an electronic device that measures resistance in an electronic component or circuit. To disable this feature, press and hold j while turning the power on. Do not exceed the rated maximum voltages between terminals or with respect to groundearth. Megohmmeter using the meter checking the battery this function tests the battery under simulated load per en61557. A digital display to show ir value in digital form. Do not use the instrument if it appears to be damaged, incomplete.
The megger technical library provides access to a range of additional content and resources such as technical guides, application notes and more. Jul 17, 2017 the megohmmeter, or megger, is a measuring device that tests high electrical resistances. A friend said his father used a megger to hunt for worms in the mud for fishing. The megohmmeter models 1210n1250n are sources of high voltage, as is the sample connected to them. The megohmmeter is in resistance mode and a limit lim0 of say 500gohm is stored in limset 1. Megger working principle types history uses of megger. The meter automatically detects if the circuit is energized, and displays the detected voltage. Caution, refer to this manual before using this meter.
For good insulation, the resistance usually reads in the megohm range. But the megger provides a much higher voltage rather than the ohm meters typical threevolt test voltage derived from an internal battery. Well email you at these times to remind you to study. The comprehensive product users manual for the amprobe amb2 megohmmeter keywords. The megger insulation tester is essentially a highrange resistance meter ohmmeter with a builtin directcurrent generator. The complete guide to electrical insulation testing. However, some plants, particularly with higher voltage ratings in equipment, use another megger product the dielectric test set. The megohmmeter will correct any setting that is entered improperly. Using megger tester for these 3 types of insulation. Be sure to follow good safety measures to prevent electrical shock. The 3m model 701 megohmmeter is designed to measure the resistance of static control work surfaces and flooring. Do not perform insulation resistance measurements if ac voltage is present on the device under test. User guide model 380260 insulation tester megohmmeter. With advanced performance, the insulation tester line is designed to be safe, simple to use and gimmickfree.
Aemc instruments considers the use of rubber gloves to be. Bm500 digital insulation tester output 100v 250v 500v three voltage, bn15 00a output of 250 v 500v v three voltage measurement range of 0. Using the instrument without its battery compartment cover may result in electric shock to the user. The supco m500 megohmmeter is specific ally designed to detect ohms with a scale that reads up to 1,000 megohms 1,000,000,000 ohms. A megger insulation resistance tester is especially useful when you have carried out electrical work on your home and want to make sure you didnt damage insulation or make a wiring mistake. We recommend using our bd loops ez detector checker to help trouble. The megohmmeter, or megger, is a measuring device that tests high electrical resistances. If an instrument is marked cat i iec measurement category i, or it is not marked with a. The megger sends voltage through the cable to calculate the amount of current flowing through the circuit, for an. The instruments are equipped with numerous advanced features and are easy to use due to the logical user interface.
Instruction manual megohmmeter danbridge electronics. In the case of an ohmmeter that value is also described in ohms. To extend battery life, the megohmmeter will shut itself off after approximately 5 minutes of inactivity. Here is how to use this useful tester on heating elements. To restore power, press any button or rotate the selector. Press and release the yellow test button to start the timer and initiate the test voltage. Go ahead and test it yourself, it wont damage the loop. Fluke 1520 users manual 12 autoshutoff the meter automatically turns off after 15 minutes of non use.