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Using a megger you check from either positive or nuetral to ground. The megger should read open (usually OL). It doesnt matter which connection you choose as long as one is ground. If the megger shows anything other than open the windings are bad.
Wiki User
∙ 8y ago
Wiki User
∙ 9y agoOn 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. Find the coil ends of the motor at the terminal block. Place one of the test leads on this coil end and connect the other test lead to the chassis of the motor. If the test shows that the motor coil is over 2 megohms the coil is fine and the motor can be put back into service.
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What kind of motor is used either on ac or dc supplies?
single phase induction motor
Can you convert single phase electric motor to three phase connection?
Three-phase motors will run on single-phase power. What they WON'T do is start. There is no easy way to re-wire such a large motor to run on a single phase.Properly sized capacitors and a special relay is sometimes used on sewage lift stations (poopie stations is what we call them) to run the 3-phase pumps on single phase.I've seen 10 hp motors used. Sometimes a lift station is needed where 3-phase power is not available The motor will not develop it's full horsepower, only about 2 thirds. A push-button can be used in place of the relay, but you will have to push the button until the motor starts then let go. If the motor stops you will need to push the button again. Usually expect several hundred micro-farads to be needed.I have used old A/C motor-run capacitors in parallel to experimentally determine the actual size (capacitance) needed. Be sure to use correct working voltage capacitors. DANGER!!! Electricity can EASILY kill you and capacitors can blow up in your face!!!I've seen crazy people attempt to rope-start three-phase motors (it works), connect phase converters, all sorts of weird stuff. In reality, single-phase 5hp motors are available, so the a good recommendation is to trade-in the 3-phase motor for a 1-phase motor of the size you need.To run a three phase equipment from a single phase source, you will need something called a "phase converter".Before you go out and buy one, find out if a single phase motor is available to match your requirements. It will probably be an easier solution for you if you can do that.Depending on your application, another option with such a large motor is to get a "Variable Frequency Drive". These are somewhat expensive but will take in a single-phase input and output 3-phase.As always, if you are in doubt about what to do, the best advice anyone should give you is to call a licensed electrician to advise what work is needed.Before you do any work yourself,on electrical circuits, equipment or appliances,always use a test meter to ensure the circuit is, in fact, de-energized.IF YOU ARE NOT ALREADY SURE YOU CAN DO THIS JOBSAFELY AND COMPETENTLYREFER THIS WORK TO QUALIFIED PROFESSIONALS.
Why do you connect a capacitor with an Ac motor?
The capacitor is used to create a second phase from the single phase power source and it is the interaction between these two phases that causes the motor to turn.
What is the type of motor used in running a lathe spindle?
230V/1Ph/50Hz 1HP (0.75 kW)Motor Capacitor start induction motor ( single phase)
Can you megger test in rain?
No you cant, simply because the rain will cause a short to ground causing low insulation (megger results)... The only way is to make sure the phase you are testing is dry and no path from phase to ground is present. usually drying the phase the sanding it down while keeping it covered will give you more realistic results or you can just wait till the rain stops :)
Why cannot test phase to phase on 3 phase motor?
Motor voltages and amperages can both be tested. The best way to test the continuity of a motor is with a megger. This will check that the motor windings are intact and if there is any voltage leakage to ground or voltage leakage to one of the other two windings in the motor. To check amperages on the motor it will have to be energized. Leave a message in discussion page as to what you are trying to do. <<>> Because there is no such thing as 'phase to phase'! However, there is such a thing as 'line to line', and this can be tested!
How many windings are in universal motor?
one windingAnswerA three-phase motor has three phase windings, normally (but not necessarily) connected in delta.
Does three phase motors have capacitors?
No, The windings in single phase and 3 phase are different. A single phase motor may use a capacitor "start" circuit to create a phase shift between windings and determine the direction it will spin. A 3 phase motor has the windings configured to create a directional rotating field which determines the rotation. The capacitor in a single phase motor is not used to convert it to 3 phase or vice-versa.AnswerIf you have access to a three-phase supply, then you alsohave access to a single-phase supply by connecting your motor to any two line conductors, or between any one line conductor and the neutral. But you MUST ensure that the motor's rated voltage matches one or other of the single-phase voltages available -that depends on what country you live in, because three-phase voltages vary from country to country. And, obviously, if you don't know what you are doing you must consult a qualified electrician.
An important difference between a universal and a split-phase motor is that the split-phase motor has?
two windings on the stator
Is it necessary to have three phase rotor windings for the transmitter and motor in selsyn motor?
is it necessary to have three phase rotor
How is direction of rotation for single phase induction motor determined?
A single phase induction motor is not self starting; thus, it is necessary to provide a starting circuit and associated start windings to give the initial rotation in a single phase induction motor. The normal running windings within such a motor can cause the rotor to turn in either direction, so the starting circuit determines the operating direction.
Is single phase connection enough for 18KW motor?
Typically, an 18KW motor would be too large to be single phase because then the windings' conductors will be too large inorder to carry such high currents. I,myself,don't think such a motor exist since a cheaper 3phase motor could be used instead.
Testing a three-phase motor finds that all the windings have the same resistance this would indicate what about the motor?
the motor is good
What happens if one phase of the 3 phase Induction motor is removed?
Is the motor 3 phase? Thats what im guessing. You would get an unbalanced load across the windings of the motor, the other 2 phase's would try to compensate and ruin the windings. 3 phase motors are obviously supposed to have 3 phase input. Weather it be in star or delta. I wouldnt try and run it if i were you!
Is a 3 phase motor a Synchronous motor?
A synchronous motor can be a type of 3-Phase AC motor, or not.A synchronous motor is defined by the period of the rotor being synchronized with the frequency of the stator windings' current. The stator windings might be 3-Phase or not (2-Phase would work).Also synchronous motors are not the only type of 3-Phase AC motors. An induction motor could also be 3-Phase AC and has a few advantages and disadvantages over a synchronous motor.
Should a starting windings in the split phase motor fail to energise what would be the result?
what will be the result if the starting winding in a split phase motor fails
How do you check single phase motor winding?
Single phase motor winding is often checked just by listening to the noise that the motor is making. An experienced person can tell if the motor is working at single phase or double phase.
