Reliance-Electrocraft / Giddings & Lewis Servo Motor Repairs
Reliance-Electrocraft is a manufacturer that utilizes standard servo technology, with a few twists. Servotech uses a specialized process to evaluate and repair all problems with your Reliance-Electrocraft servo motor. Our finished product will run as if the factory just sold you a new motor.
Because Reliance-Electrocraft servo motors exist under so many different manufacturer’s labels – Reliance-Electrocraft – Giddings & Lewis – Allen Bradley – it is an incredible challenge to keep accurate motor data specific to each manufacturer’s iteration. We have an extensive array of original technical data sheets and a good working knowledge of motor specifications. Without this information, a motor can only be repaired to “running” condition.
Our goal is to supply you with a Reliance-Electrocraft servo motor that is not only repaired but has been refurbished back to like new condition. Our repair procedure includes these steps:
1. Evaluation of Your Reliance-Electrocraft Servo Motor
Servotech inspects all electrical and mechanical components. Reliance-Electrocraft servo motors have unique encoders, and armature windings. During our evaluation, we examine:
- Magnet and banding material integrity of the rotors
- Housing fits
- Worn output shafts
- Corroded and/or broken flanges
- Absolute step voltage signals integral to the hall sensors or encoders
- Bearing fits
A typical Reliance-Electrocraft when it arrives in the shop, and then after we service it.
2. Motor Repairs
We manufacture or repair any problems found during our evaluation, fixing any part that does not meet the factory specifications. Often we:
- Re-epoxy broken magnets to rotors followed by re-banding (process of holding magnets onto rotors so that the centrifugal force of rotation does not cause them to dislodge).
- Re-manufacture a new Reliance-Electrocraft servo motor front flanges and bearing fits using factory dimensions.
- Repair all the windings. Both AC and DC servo motors windings are washed, baked and tested.
- Repair or replace brush holders and Bake-O-Lite insulation tubes on DC motors.
Defective Reliance-Electrocraft endbell and a replacement.
3. Preliminary Servo Performance Testing
Throughout the assembly process each Reliance-Electrocraft servo motor repair will be meggered numerous times. Some of our tests include:
- Test to confirm there are no grounded electrical parts in the servo motor (megger test).
- Evaluate the need for encoder replacement with brand new state of the art encoders that couple commutation and position into a single unit.
- All AC stators are surge tested to at least 1500 volts.
- After the baking process DC servo motor armatures go through a bar to bar test. This test reveals if there are any shorts or opens in the winding.
4. Motor Assembly
The next step for the Reliance-Electrocraft motors is reassembly. Our process improves the internal motor components and protects them from contamination. Rebuilt motors utilize:
- High-grade sealed bearings – we feel that sealed bearings promote a longer life for Reliance-Electrocraft servo motors. Seals keep dirt and contaminants from polluting the bearing races.
- Double lip seals in the front flange – these seals keep coolant from getting to the bearing.
- All fits are sealed with a highly-proven gasket eliminating gel. O-rings, gaskets and connectors are replaced to ensure that your Reliance-Electrocraft servo motor is protected from liquid contamination.
- Two-part epoxy coating for an added protection – the same coating used on Navy submarines.
Oscilloscope print out of absolute step voltage, a special signal proprietary to Reliance, Electrocraft, and Giddings & Lewis motors. Below, old style feedback, broken beyond repair.
5. Final Testing on Reliance-Electrocraft Drives
The final step in the Reliance-Electrocraft servo motor repair process is to run your motor on a Reliance-Electrocraft drive just like the one in your machine. Reliance-Electrocraft servo motors are run at full voltages and full currents of the motors capability. This provides accountability to all the previous steps in our servo motor repair process. Motors do not pass the final test step unless repairs were done correctly. New drives are purchased regularly to stay on top of changes in manufacturer’s technology, and to keep our final test procedures accurate.