First turn off all power to the equipment, then lock out the disconnect switch and tag it. Measure all power leads inside the unit for any voltage to ground. If no voltage is being read, Then place your meter on a low ohms scale.
Full Answer
How do you test a DC motor with a Megger?
Connect one lead of the DC motor to the megger probe and the other lead from the megger to the frame or metal case of the DC motor. Press the power button on the megger or turn the hand crank. The battery unit will take a few seconds to analyze the voltage travel and soon a reading should appear on the LCD screen.
What does a megohm mean on a motor?
A megohm measurement is used to measure the winding’s Insulation Resistance (IR) to ground. The megohm result indicates how dirty, contaminated or wet the windings are (all referred to as “dirty”). If the megohms are below certain levels, the motor should be scheduled for reconditioning.
What is a Meg ohm test?
In cases such, a meg ohm test or megger may be required. The megger tester uses a high voltage, generally in the 1000 to 10,000 volt range to identify insulation leakage in motor coils and adjacent wiring.
How can I increase the ohms value of my motor?
Sometimes warming up the motor can reduce the moisture content and raises the ohms value reading to an acceptable level. Ohming a combination of any two windings should read exactly the same ohms value, as any other two windings compared to another two windings.
How do you test a DC motor Megger?
How to Test a Motor using Megger?Place one megger lead on the ground terminal or wire and place the other lead on one of the phase wires or terminals.Press test on the megger.A very high resistance reading (greater than 10 megohms) will indicate the motor insulation is good.More items...
How do you ohm out a DC motor?
Attach the clip of the black lead wire to the DC motor and run the black motor wire to the battery. Attach the red and black lead wires to the volt meter on the red and black terminals respectively. Look at the display on the voltmeter and check for the ohm reading.
How do you test a DC golf cart motor?
0:0010:28Testing 36 volt golf cart motor with 12 volt battery - YouTubeYouTubeStart of suggested clipEnd of suggested clipGet this thing up on a floor jack here small one i'm gonna put some jack stands up underneath hereMoreGet this thing up on a floor jack here small one i'm gonna put some jack stands up underneath here right.
What is the acceptable Megger reading for a DC motor?
A general rule-of-thumb is 10 Megohm or more. This is how the test works: DC voltage of 500 or 1000 V is applied between the windings and the ground of the motor. During the measurement and immediately afterwards, some of the terminals carry dangerous voltages and MUST NOT BE TOUCHED.
How do I know if my DC motor is bad with a multimeter?
1:153:02How to check a DC drive motor from a treadmill using a multimeterYouTubeStart of suggested clipEnd of suggested clipThere. So I'm going to flip the meter on two ohms. And we're going to put one probe in one line if IMoreThere. So I'm going to flip the meter on two ohms. And we're going to put one probe in one line if I tell you what we'll put the red probe in the red wire. And the black and the black wire. And
What should the resistance of a DC motor be?
windings (due to their movement through the magnetic fields). is 4.95V, back EMF is about 4.55V during normal running. through the winding will be much larger (about 2.5A initially).
How do I know if my electric golf cart motor is bad?
You have enough going on in your life without your golf car refusing to start when you turn the key in the ignition. If your golf car won't start, is slower than it used to be, or is experiencing other technical problems, you could have a bad motor on your hands.
How do you test a motor for continuity?
Start by completely disconnecting the spindle motor from all power sources. Check each wire, including T1, T2, T3 and the ground wire. If the reading is infinite, your motor should be fine. If you get a zero reading or any continuity reading, you have either a motor problem or a cable problem.
What are the 4 terminals on a golf cart motor?
If you're unsure if it is working, it is simple to test. There are four terminals on a solenoid: usually two large and two small. The small terminals are connected to the battery, and the large terminals are connected to the motor. Disconnect all wires from the two large terminals.
How do you meg a motor with a multimeter?
4:339:26How To Troubleshoot 3 Phase Motor With A MultiMeter (3 ... - YouTubeYouTubeStart of suggested clipEnd of suggested clipIt's basically the same thing as ol and your motor would be bad one thing you must take into accountMoreIt's basically the same thing as ol and your motor would be bad one thing you must take into account is the temperature of the motor. Before performing any of these tests.
What voltage should you megger a motor?
The minimum test result should be the motor's rated voltage in kilo- volts, plus 1. For example: A 460 volt motor should have a minimum test result of 0.46 (kV)+1.0= 1.46 Meg. A 4160 volt motor should be 4.16 (kV)+1= 5.16 Meg.
What are good megger readings?
Anything reading between 2 megohms and 1000 megohms is usually considered a good reading, unless other problems have been noted. Anything less than 2 megohms indicates an insulation problem.
How can you tell if a DC motor is bad?
Measure the resistance between the motor terminals and compare it with a known good motor (or the datasheet). If the coils have melted, they will have shorted and you'll see a lower resistance. Or they will have broken altogether, and you'll read infinite resistance.
How do you test a 12 volt DC motor?
2:596:32Testing 12 volt DC motors anywhere. How to test marine or car ... - YouTubeYouTubeStart of suggested clipEnd of suggested clipYou want to make sure your pin is touching against the terminal. They're setting their good spreadMoreYou want to make sure your pin is touching against the terminal. They're setting their good spread apart. And then my orange wire i'm going to do that with. Positive.
Do DC motors have resistance?
A DC electric motor spinning at 4500 RPM draws 3 amps of current with 110 volts measured at its terminals. The resistance of the armature windings, measured with an ohmmeter when the motor is at rest, unpowered, is 2.45 ohms.
How do you test a motor with a multimeter?
Set your multimeter to Ohms. Start by completely disconnecting the spindle motor from all power sources. Check each wire, including T1, T2, T3 and the ground wire. If the reading is infinite, your motor should be fine.
What voltage do you use to test a DC motor?
In cases such, a meg ohm test or megger may be required. The megger tester uses a high voltage, generally in the 1000 to 10,000 volt range to identify insulation leakage in motor coils and adjacent wiring. By following a basic set-up you can test ...
What is the least amount of ohms on a megger?
The further the needle on the meter is deflected, the least amount of meg ohms is in the windings or wiring. In other words, on a hand crank type megger, the further the needle is deflected to the right, the worse the resistance is in the DC motor.
What does 999 ohm mean?
A meg ohm reading of 999 meg ohms or greater means an almost perfect insulation of the windings and wiring. Readings of less than 1 meg ohm should be considered as a problem or serious resistance breakdown of the wiring or motor windings.
What type of brush is used to test a DC motor?
Perform this procedure a number of times as most DC motors use a carbon brush and copper commutator to conduct the electrical power to the armature. This method will ensure that the separate windings of the armature are being tested.
Can a DC motor controller be damaged?
Some DC motor controllers can either give false readings or become damaged by the reversal of current flow into the control mechanism of the high testing voltage. Testing a DC (direct current) motor may take more than just a simple volt ohmmeter. Some DC motor controllers can either give false readings or become damaged by the reversal ...
What does ohming a 3 phase motor mean?
Ohming a 3 Phase Motor. Ohming a combination of any two windings should read exactly the same ohms value, as any other two windings compared to another two windings. Any different ohms value indicates a problem with the winding. Example: ohm terminal 1 to 2, or 1 to 3, or 2 to 3, all should read the same ohms value.
How to measure winding resistance?
If no voltage is being read, Then place your meter on a low ohms scale. Determine if motor is single phase, or three phase. Then disconnect motor leads from motor and proceed to ohm out each terminal from common to start and common to run, for a single phase motor. Then place one meter lead connected to start terminal, the other meter lead connected to run terminal, to get total winding resistance thru both windings. The total winding resistance should add up to both the run & start winding resistance readings added together.
How long to record a meg phase to ground?
Meg phase to ground for 10 minutes, Record values at 30 sec, 1 min, and 10 minutes so you can calculate DAR and PI. Temp correct to 40C. A proper winding resistance test would be done with a winding resistance test set or a DLRO.
Do you need a high voltage for a phase to phase test?
Phase to phase test should have a low resistance and there is no need for the high test voltage used for meg-ohm testing. If your usual digital meter with a low test voltage can't read any continuity through the winding they are open-circuited.
What is a megohm?
A megohm measurement is used to measure the winding’s Insulation Resistance (IR) to ground. The megohm result indicates how dirty, contaminated or wet the windings are (all referred to as “dirty”). If the megohms are below certain levels, the motor should be scheduled for reconditioning.
What is a PI motor?
PI (Polarization Index) and DA (Dielectric Absorption) are ratios of megohm measurements done at different times. PI is the ratio of the megohms at 10 minutes and 1 minute.
What is a PI in a form coil?
PI is most commonly used with form coil machines, and usually includes a megohm time series graph with multiple recorded megohm values. The graph can provide additional information about the condition of the insulation system and indicate if the insulation is brittle or delaminated. DAR and PI results may be tracked over time in maintenance ...
How to check if electric golf cart is running?
It sounds absurd, but if your electric golf cart is not running, the very first thing I would check is the reset button on the side of the motor, if your cart is so equipped. Check around the outside of the motor and see if you can find a small button to press. This is usually a safeguard against overheating.
When did golf carts start having separate excited motors?
In 1999, some golf cart manufacturers started offering Separately Excited Motors. Sepex (Regenerative) Motor carts have a toggle switch F&R device as opposed to the lever-action. In addition to this identifier, they have a tow/run or tow/maintenance switch which cuts power to the controller. Most of the modern-day carts are equipped ...
What is a series motor?
A series motor has field and armature windings that have the power fed to them from the same source, either in series or parallel. A SePex motor, as the name indicates, is a motor that has a separately excited field and armature windings. These two motor functions are sent to the PDS or DCS giving greater control over the motor.
What is wrong with my electric golf cart?
Electric golf carts are usually trouble-free and do their job efficiently and with no fuss, but sometimes you suspect your golf cart is experiencing a problem. If the speed seems to be off, or your cart gives off a burning wire smell, your golf cart motor might have a problem. Using a multimeter, a jumper wire, and a 12-24 volt power source, ...
Why is it important to test a motor before replacing a controller?
This is an important test to do on your motor before replacing the controller because a short could damage the new controller irreparably. Please note that this test will not find a short in the armature. Note that continuity testing is not directional, so it doesn’t matter if the red and black are reversed.
What is a golf cart?
Golf carts are also known as golf cars. The term "cart", in its purest sense, refers to a vehicle that does not travel under its own power. Golf cars, however, are most commonly referred to as golf... link to Club Car DS Wiring Diagrams 1981 To 2002.
