Motor Testing Pdf

The basics of motor testing

So when a motor fails to operate it may not be obvious what the problem is. With power disconnected and locked out, bio waste management pdf attempt to turn the motor by hand.

Is there any problem for this? The windings all three in a three-phase motor should read low but not zero ohms. The motor is refrigerant cool. It does not make a distinction between Delta and Wye systems.

Often good operation can be restored by oiling front and rear bearings without disassembling the motor. It is basically the grease got lost its viscosity. The clamp-on ammeter reading will tell you where you stand on this continuum.

Motor testing pdf

If these readings vary by a few volts, it may be possible to equalize them by rolling the connections, taking care not to reverse rotation. The value of no load current we are getting is not matching with the data sheet value. Knowledge of the basics together with powerful new test equipment vastly simplifies the job. This site uses Akismet to reduce spam.

Knowing some basic methods and techniques along with having a few test instruments handy helps detect and diagnose problems with ease. Excess current causes heat, which must be dissipated. It provides analysis data for both the electrical and mechanical characteristics of the motor while in operation. Move the switch from side to side and, with a trigger switch taped so it remains on, press on the brushes and turn the commutator by hand.

But rather than the typical three-volt test voltage derived from an internal battery and present at the probes, the Megger provides a much higher voltage applied for a proscribed length of time. The use of a splitter fixes the problem. Additionally, unsuspecting individuals could be exposed to hazardous high voltages. In vibration report mostly they say high frequency components in bearings and recommend us to grease.

If the motor itself has developed a fault, the fault may be a burnt wire or connection, a winding failure including insulation deterioration, or a deteriorating bearing. Facebook Linkedin Linkedin Twitter. Why double grounding is needed for motors? When an electric motor fails to start, runs intermittently or hot, or continually trips its overcurrent device, there my be a variety of causes. Hello I ordered a kW three-phase electromotor to make.

Please find some of the answers for your question. To do this, shunt the relevant conductor s to ground and to each other before reconnecting the power source. Clamp-on ammeters are user friendly. Just open the spring-loaded jaws, insert either the hot or neutral conductor, then release the jaws. It circumvents such difficulties by measuring the magnetic field associated with the current, displaying the result in a digital or analog readout calibrated in amperes.

This is especially true if there is ambient moisture or the motor has been unused for a while. The analysis is presented in simple readouts, making it easy to gauge the operating performance and determine if adjustments are needed before failures cause an operational shut down. If we check resistance and inductance before rewinding and if we check after some months and if we find a variation in Resistance and Inductance what may be the reason?

Sometimes the trouble lies within the power supply, including branch circuit conductors or a motor controller. Other developments include integrating multiple instrument functions into one unit. Small universal motors, such as those used in portable electric drills, can contain extensive circuitry including a switch and brushes. In a three-phase hookup, all legs should have substantially equal voltage readings, with no dropped phase. If any international standard kindly advise.

Motor testing pdf

Scope Of Motor Testing

Motor testing pdf

In an industrial facility, the recommended procedure is to perform periodic tests and record the results so damaging trends can be detected and corrected to prevent an outage and extensive downtime. Preliminary tests generally are done using the ubiquitous multimeter. If there is no voltage or reduced voltage, work back upstream. Hi Edvard kindly some info related to verticalmotors.

Motor testing pdf

Electric motors have had a reputation for being a mix of science and magic. Testing and commissioning procedure for electric motors. The information for testing and commissioning of motor was informative very useful. Amperage or current readings are useful in motor testing as well. During construction site, voltage may varies.

Take readings at accessible points including disconnects, the motor controller, any fuses or junction boxes, and so on, back to the over-current device output at the entrance panel. Does this motor need a solo run?

The basics of motor testing

The insulation resistance tester resembles a conventional ohmmeter. Your email address will not be published. If possible, disengage the load. The smaller the motor, the higher this reading will be, but it should not be open. As motors age, the current drawn generally rises because winding insulation resistance drops.

The leakage current through insulation, expressed as resistance, is displayed so it can be graphed. How many of us still use that arrangement? Need checklist of Mechanical Sequence for motor Solo Run test.

Motor testing pdf

What level of inspection do I have during construction? The correct settings, connection procedures, test durations and safety precautions must be implemented to avoid damaging the equipment or electrocuting the operator or coworkers. It happens due to long running hours, over heat, may be high ambient, Etc.

Any fluctuation in the digital readout may point to a defect. Multimeters always have a current function, but there are two problems with it.