Are you searching for a reliable and affordable motor rewinding service in Vietnam? Look no further than Hai Ha M&S, located in Haiphong. With over 15 years of experience as one of Vietnam’s most esteemed electric motor suppliers, we offer bespoke electric motor rewinding services to meet your needs.
As an accredited member of The Association of Electrical and Mechanical Trades, we have extensive experience in providing electric motor rewinding services for a wide variety of motors. We offer free testing and quotations and will guide you through the rewinding process, ensuring that you understand how to get the most out of your motor.
Rewinding is often the fastest and most cost-efficient motor solution, and we are ready to help. Contact us using the form below or by calling +84 388 441 654 to learn more about how we can assist you in rewinding your motor.
What is motor rewinding?
Motor rewinding is a process that involves re-winding the coils in electric motors that have experienced a deterioration in their efficiency. The goal of this process is to improve the motor’s efficiency and prolong its lifespan, which can be a more cost-effective solution than replacing the motor altogether. Rewinding can help restore the motor’s original performance, reducing energy consumption and improving overall efficiency.
How to determine if your electric motor needs a rewind
1. Rule out obvious causes
To determine if your motor needs a rewind, it’s sensible to first rule out any obvious causes. Start by assessing the condition of your motor and make a note of any physical defects that the motor has. Obvious issues could include broken mounts, scorch marks, and contamination from water or rust. After you’ve made a preliminary inspection of the component, try rotating the shaft by hand. If you’re unable to move the fan, then an obstruction or failed bearings could be the issue, as opposed to a winding issue.
2. Testing motor windings
Once you’ve determined that the motor is not failing due to an obvious mechanical reason; measure winding resistance, check 3 phase windings by supplying low voltage and check the currents are balanced.
3. Measure insulation resistance
Insulation resistance (IR) is another measurement that you can use to determine if your motor is in need of a rewind or not. These measurements can be taken between windings, and between the windings and earth point. The IR value should preferably be greater than 100M ohms and a minimum of 2M ohms. A measurement of fewer than 2M ohms indicates that the insulation is deteriorating, or has failed already. Many winding faults can be attributed to low IR. Contamination, power surges, excessive heat, vibration or damaged wires can all contribute to creating a low IR. In some cases, a thorough clean and dry can help to fix these issues, but often an electric motor rewind is the most efficient route to resuming optimal performance.
Benefits we offer with our motor rewinding services:
- Free local collection and delivery service for all motor rewinds
- Free testing and quotation
- 24-hour service if required
- Full 12-Month Parts and Labour Guarantee
- Electric motor rewinding service near you
- Small electric motor repair near you
As one of the longest established suppliers of electric motors & industrial fans in the Vietnam, we are proud to offer an unbeatable rewinding service across an unrivalled range of motors.
Contact us at +84 388 441 654 via the form below to take advantage of our local collection and delivery service for all motor repairs, free testing and quotes, and a full 12-Month Parts and Labour Guarantee.
Why does a motor need rewinding?
In addition to improving efficiency, motor rewinding prevents motor breakdowns and extends the life of motors. Motor rewinding can also revitalise a motor if it has previously burnt our. Pairing motor rewinding with replacing older or more damaged component parts can greatly improve your motor’s sustainable efficiency and overall lifespan.
How is motor rewinding done?
Most motor rewinding processes generally involve three simple steps. First, the winding coils are removed or stripped, depending on the model. Next, new winding coils are often inserted before being insulated. Finally, the motor is rewound, and the insulation paper lining the stator is replaced if necessary. Below we’ve detailed our tried and tested motor rewinding process we’ve been refining for over 90 years, enabling us to provide our customers with unrivalled reliability and efficiency.
1. First Inspection
You can send us the motor, or if you’re local to us we’ll pick it up from you. We will then inspect your motor to determine what the issue is. We may ask you questions related to how often the motor is used, what kind of operating environment it is in, and whether you’ve had any rewinds performed before. This will help us determine the source of the issue so that we can select the right course of action.
2. Dismantling
Unless the issue is evident immediately, it is likely that we will need to dismantle the motor to examine it fully. Our experienced team has dismantled and re-assembled hundreds of motors, so your machine will be in safe hands. After this has been done we will be able to determine the source of the issue and be able to offer you a bespoke quote for the rewind or repair. We are not obliged to re-assemble items that have been dismantled for quotation purposes only.
3. Removal of Winding and Cleaning of Core
If you decide to go ahead with the motor rewind then our team will get on with the task of recording the winding detail on data sheets, before carrying out core loss testing and then removing the old winding. It’s important for the stator core to be properly cleaned at this point so that the motor is properly prepared for rewinding.
4. Rewinding the Motor
Once the motor has been properly prepped we’ll get on with the rewinding, ensuring that the original winding configuration is duplicated for optimal efficiency. In some cases, our engineers may be able to identify a different style of winding that will match the motor’s performance. Once the rewinding is completed, we’ll conduct a series of tests to ensure that all is performing as it should be, before re-assembling the motor.
5. Collection or Delivery
Once the job is completed we’ll happily arrange a free delivery (if you are local to us), or enlist a trusted courier service to deliver your motor. Alternatively, you’re more than welcome to pick up the motor from our shop yourself.
How to rewind an electric motor
1. Clean work surface
Make certain to clean your working area thoroughly, removing any dirt or debris that may have accumulated. Be particularly meticulous in removing any metal shavings, as they can be attracted to the magnetic components of your electric rewind and create problems in the future.
2. Dismantle Motor
It is important to mark all parts that can be removed. Pay attention to the position of pulleys, couplings, and other components. Examine the bearing housings and make a note of the bearing sizes, taking into consideration nuts, bolts, washers, screws, and other small parts. Keep these parts secure and in a safe place.
3. Take Note of the Motor Windings
Inspect the winding connections carefully and create a drawing if needed. Record the type of winding, including the number of slots, coils, and poles, for future reference.
4. Remove Coil from Stator
Cut one end of the winding off, taking care not to damage the stator. Use heat if necessary to soften the varnish that secures the coils in place, and carefully pull the coil out from the end.
5. Insulate Stator
Thoroughly clean the stator of all old insulation. Inspect the slots for any sharp edges and file them down if necessary. Install the appropriate thickness of insulation to re-insulate the slots.
6. Source Correct Replacement Wire
Obtain the same gauge of wire that was used in the original windings. Count the number of turns in the coils of the original winding. This will ensure that the new winding matches the original specifications.
7. Recreate Original Winding Coils
Using the same gauge wire as the original winding, wind a new set of coils to match the size and specifications of the original winding. Connect the coil lead ends according to the original winding connections. This will ensure that the new winding performs correctly.
8. Varnish Windings
After winding the new coils, perform insulation and continuity tests to ensure that the new winding is sound. Once the tests are completed and any issues have been resolved, impregnate the windings with varnish and cure them in an oven. This will provide additional insulation and protection to the windings.
9. Reassemble Motor
Replace the old bearings with new ones on the rotor. Insert the rotor back into the stator. Reinstall the endplates, making sure to align all the location indicators that were made during the motor disassembly. Test the motor to ensure it functions properly. Finally, repaint the motor to protect it from environmental factors.
Small Electric Motor Repair Near You
Our complete operations are housed in our current location in Haiphong. We maintain all of our stock at this facility, and we also provide electric motor rewinding and repairs for our valuable customers. Whether you are located near our Hai Ha M&S workshop or at a more distant location, we are pleased to offer assistance with small electric motor repairs and other services as needed.
