Troubleshooting Index
AC Troubleshooting

The following steps may be taken to troubleshoot an AC Motor and Controller system:

Step 1: Check the motor's smell. If there is a burning smell, replace the motor immediately.

Step 2: Check the motor's input voltage. Ensure wires are not damaged and the proper power supply is connected.

Step 3: Listen for loud vibration or squeaking noises. Such noises may indicate damaged or worn-out bearings. If possible, lubricate the bearings, otherwise replace the motor completely.

Step 4: Check for overheating. Use compressed air to rid the motor of debris, allow to cool, and restart.

Step 5: AC Motors that make an effort to start but fail, may be a sign of a bad starting capacitor. Check for any signs of leaking oil, and replace the capacitor if this is the case.

Step 6: Ensure the application the motor is rotating is not locked up. Other mechanical components may be the cause of failure or poor performance. Do this by disconnecting the mechanism and try running the motor by itself.

Brush DC Troubleshooting

Note: Exercise caution when troubleshooting your Brush DC Motor. Ensure safety guards are in place, disconnect any power, and discharge all capacitors prior to inspecting the Brush DC Motor.

Problem: After installation, Brush DC Motor does not start.

Solution: Ensure the Brush DC Motor is correctly wired, and verify the appropriate voltage is being generated from the controller. If necessary replace the fan guard, and check to make sure the armature is not rubbing against the magnets due to misalignment. The Brush DC Motor may need to be replaced. Depending on the original cost of the motor, the brushes can be replaced. For Anaheim Automation Brush DC Motors, the entire motor is replaced as it is the most cost-effective approach.


Problem: Brush DC Motor loses power while running.

Solution: Check the load being applied to the motor. Changes in load may be too much for the Brush DC Motor to handle. Measure the amp draw next to the motor's full load amp rating to be sure the Brush DC Motor is appropriately sized for the application. Also check the settings on the controller, and the armature. Torque and compensation settings may be slightly off, and the armature needs an open connection.


Problem: Brush DC Motor fails to start after having been working.

Solution: If this is the case, the brushes may have worn down and are unable to interact with the commutator. Take apart the Brush DC Motor and check both the commutator and armature for any burnt bars or a burnt coil. Finally, ensure the voltage is emitting out of the controller.


Problem: Brush DC Motor is not accelerating quickly enough.

Solution: Check the length of the brushes to ensure they are not worn out. Look for any defective bearings (bearings generating loud noise is a sign); replace or lubricate bearings if needed.


Problem: The Brush DC Motor is running in reverse.

Solution: Double check the wiring arrangement, and interchange the two leads.


Problem: The Brush DC Motor makes a clicking sound.

Solution: Remove burr from the armature with a commutator stone.

Brushless DC Troubleshooting

There are a few things that can cause your Brushless DC Motor to stop running or run incorrectly. The Hall sensors of the motor can be bad or shorted. One technique that can be used to check if the Hall sensors are bad is to pull up each Hall with a 10k resistor connected to 5 volts and check each Hall with an oscilloscope while spinning the shaft. Please make sure that the hall power is also connected to the 5 volt supply.

You will need to repeat this for each Hall, meaning you will have to do them individually. A low and high signal should appear on the scope as you spin the shaft manually. Keep in mind, that it does matter what value is used for the resistance, it all depends on the amount of current your Halls can take. If you find that your Hall Sensors are working correctly, you can move onto the next step and check the Phases of the Brushless DC Motor. Hook up the motor to a Driver/Controller. With an oscilloscope, check each Phase to see if a switching signal is present. If you find that the Phases are also doing what they are suppose to be, move on. The bearings of the motor could be a possible problem along with internal shorts of the motor and if the motor is still not working properly, you might want to consider getting a new motor.

Encoder Troubleshooting

Problem: No output

Solution: No output may be a result of various factors. Steps can be taken to ensure the proper functionality of the encoder. No mechanical movement results in any signal being output from the encoder. To correct this issue, observe if the encoder is rotating. Verify all wring between the encoder and the driver/controller is correct and the appropriate voltage supply is used. Having loose connections or improper voltage supply may not allow the encoder to function properly. Finally, ensure the correct signal type (e.g. open collector, pull-up, line driver or push-pull) is being used for your application. If the problem persists, swap encoders, if possible, to determine if the encoder is the issue.


Problem: Unable to find index pulse

Solution: The index pulse, or reference marker, is a once per revolution output of an encoder and is best found using an oscilloscope. Verify all the wiring between the encoder and the driver/controller is correct and the appropriate voltage supply is used. If that does not solve the issue, try lowering the RPM of the motor, as the driver/controller may not be able to identify the index pulse at very high RPM values.


Problem: Count output indicates incorrect direction

Solution: If the count output indicates an incorrect direction then check for the wire configuration. See if any wires are reversed. If they are reversed, simply swap wires.


NOTE: If your application is using index, reversing the wire configuration causes the reference alignment to also change. If so, please make the appropriate changes to your application.


Problem: Encoder is not rotating

Solution: When encoders are exposed in open environments, dust and debris particles may accumulate around the shaft. Simply clean the exposed area and ensure that there are not objects obstructing the encoder from rotating.


Problem: Noise Interference

Solution: To improve the noise immunity of encoders it is strongly advised that no other electrical equipment be nearby or be kept at a fair distance. Encoder cables should also be shielded and proper wires should be grounded to minimize electrical noise.


Problem: Distorted or incorrect output

Solution: Distorted or incorrect output can be any combination of loose wiring connections, encoder output not compatible with driver/controller, electrical noise or improper alignment. Check for wire connections, compatibility issues with the encoder and the driver/controller, alignment of the encoder and the shaft to solve this issue.


PLEASE NOTE: Technical assistance regarding its Encoder line, as well as all the products manufactured or distributed by Anaheim Automation, is available at no charge. This assistance is offered to help the customer in choosing Anaheim Automation products for a specific application. However, any selection, quotation, or application suggestion for an Encoder, or any other product, offered from Anaheim Automation's staff, its' representatives or distributors, are only to assist the customer. In all cases, determination of fitness of the custom Encoder in a specific system design is solely the customers' responsibility. While every effort is made to offer solid advice regarding the Encoder product line, as well as other motion control products, and to produce technical data and illustrations accurately, such advice and documents are for reference only, and subject to change without notice.

Gearbox Troubleshooting

Problem: Gearbox Becomes Hot
Solution: The exterior temperature of the gearbox may become hot due to several reasons. Please refer to the following information, take the necessary steps to solve this issue. If the gearbox temperature is excessive, please consult the manufacturer.

1. Ambient temperature is above advised level - If the ambient temperature is too high, it may diminish the efficiency of the gearbox. Install a cooling fan or move the application to a more viable location.

2. Proper ventilation - Proper ventilation is necessary, not only for the gearbox but for all electrical/mechanical equipment to function properly. Ensure that there is adequate air flow in the area of the equipment to allow for system cooling.

3. Improper shaft alignment - The first step is to check the alignment of the input shaft of the motor to the gearbox. It is necessary that the input shaft of the motor be aligned with the gearbox to ensure the proper use of the gearbox.

4. Overload - Decrease the load of the gearbox and observe if the temperature lowers. If not, your application may require a larger gearbox model.

5. Lubrication – Poor lubrication for the bearings and gears. Consult with the manufacturer regarding warranty information.

6. Improperly mounted bearings - Reassembly may be required of the gearbox. Consult with the manufacturer regarding warranty information.

Problem: Loud/Vibration Noise
Solution: Loud or vibration noises can be due to many different sources discussed in this section.

1. Improper installation - Improper installation may be a result of loose bolts or misalignment between the motor and gearbox. Tightening loose bolts and aligning the motor and gearbox may solve the issue of excessive noise.

2. Input speed too high - Lowering the input speed may help reduce the noise.

3. Overload - Decreasing the load may help reduce the noise. If not, a larger-sized model gearbox will be required.

4. Worn or damaged bearings - Worn or damaged bearings may need to be replaced. Consult with the manufacturer regarding warranty information.

5. Lubrication - Gears/bearings need to be properly lubricated for cohesiveness. Consult with the manufacturer regarding warranty information.

Problem: Input/Output Shafts Do Not Rotate
Solution: Before going through the below instructions, ensure the motor shaft rotates to isolate any problem with the motor or gearbox.

1. Proper installation - Ensure that all bolts connecting the motor to the gearbox are securely fastened.

2. Gear teeth are worn - Need to replace worn gears. Consult your dealer for warranty information.

3. Gears in locked position - Gears may need to be replaced due to wear and tear. Another possibility would be that a foreign object may need to be removed from within the gearbox, causing the gears to be in the locked position. Consult your dealer for warranty information.

Problem: Gear Teeth Wear
Solution: Wear and tear on gearboxes is natural occurrences. Proper use and system maintenance can help extend their lifetime of the gearbox.

1. Proper installation - Ensure that all bolts connecting the motor and the gearbox are securely fastened.

2. Excessive load - Wear and tear on the gear is caused by contact with other gears. Reducing the load will lower the tension the gears make with one another. If a higher load is required, using a larger gearbox may be necessary.

3. Input speed too high - Lowering the input speed may help reduce the amount of wear and tear on the gears.

4. Ambient temperature is above the advised level - If the ambient temperature is too high, it may diminish the efficiency of the gearbox. Installing a cooling fan, or moving the application to a more viable location may resolve this application.

HMI Troubleshooting

Sometimes when the PLC and HMI are hooked up together and operating under the EV5000 software, a PLC error may appear. To troubleshoot the error, simply use a numeric display and set it to the PLC register the data is being written to. If this PLC register comes back with random register values, this indicates that the HMI did not deliver the information to that register. If it was sent correctly, then the numeric displays should show the information that was sent. This is a very simplistic way of solving HMI/PLC errors. See Anaheim Automation's Video Tutorials for more help with programming an HMI.

Stepper Troubleshooting

Problem: Intermittent or erratic step motor or stepper driver function.

Solution: This is the most common cause of failure and one of the most difficult to detect. Start by checking to ensure all connections are tight between the step motor and the stepper driver and controllers. Evidence of discoloration at the terminals/connections, may indicate a loose connection. When replacing a step motor, stepper driver or driver pack, or controller in a motion control system, and be sure to inspect all terminal blocks and connectors. Check cabling/wiring for accuracy. Stress step motor wiring and connections for poor conditions and check with an ohmmeter. Whenever possible, use Anaheim Automation's shielded cables for step motor wiring.


Problem: Poor system performance.

Solution: Check to see if the wire/cables are too long. Keep step motor wire/cables less than 25 feet in length. For applications where the wiring from the step motor to the stepper driver exceeds 25 feet, please contact the factory for instructions, as it is likely that transient voltage protection devices will be required. Another possibility is the step motor lead wires are of a gauge too small. Do not match your cable wires to the gauge size of the step motor lead wires, this is a common mistake. To avoid this mistake, Anaheim Automation suggests using its shielded cable for such wiring purposes (purchased separately). Additionally, check the age of your step motor, as with time and use, step motors lose a portion of their magnetism which affects performance. Typically one can expect 10,000 operating hours for step motors (approximately 4.8 years, running a one eight‐hour shift per work day). Also, make certain your step motor and driver combination is a good match for your application. Contact the factory should you have any concerns.


Problem: The step motor is stalling.

Solution: In some cases, stalling of a step motor causes a large voltage spike that often damages the phase transistors on the driver. Some drivers are designed to protect themselves from such occurrences. If not, Transient Suppression Devices can be added externally. Consult the factory for further information.