bad motor or bad controller -- how can I tell?

11 years 8 months ago #29525797 by neumotiv
My 3-phase motor seems to be doing nothing in either direction.
Using Roborun+, my Motor Command ramps up and down as you might expect to the desired slider setting. But in one direction (and NOT) the other the Motor Power runs off the scale until a limit is exceeded and then drops back to zero. Since Roborun seems to be monitoring actions OK, can I assume the motor is likely bad (and NOT the HBL2350 controller)?

Q: In other words, is the Motor Power monitoring actual power being delivered to the motor by the FET output stages(?)

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11 years 8 months ago #29525803 by roboteq
If the motor doesnt move, it can be one of few things:

1- Wrong or faulty wiring in motor. You can test this by applying power alternatively between two of the 3 wires. There are 3 combinations: UV, UW, VW. Use a current limited desktop supply. Verify that the rotor is attracted to a pole for each of these combinations

2- Faulty hall sensor. Use a voltmeter and measure the voltage on each of the output (with the sensor connected to the controller). Verify that each sensor goes to 0V and 5V as you rotate slowly the shaft, with no other voltage inbetween. YOu can also get an idea wether the hall sensors are working by enabling the counter in the roborun chart and verify that count goes steadly up or down as you slowly rotoate the motor in one direction or the other.

3- Wrong motor wire connection to the controller. There are 6 possible ways to connect the 3 motor wires to the 3 controller output. Only one gives smooth rotation. Sometimes as second combination allows the motor to turn. All others wont work.

4- Hall sensors not positioned 120o apart. Some motors have sensors 60o apart. This is quite uncomon, however. To test, use the voltmeter to see the hall sensor transitions and verify that they occur as shown in the diagram in the controller datasheet.

5- Faulty controller. While they are being tested before shipping, this is always a possiblity. After verifying that the counter works, apply 100 to 200 power with the slider. Verify that the motor is locked in one position if it is not turning. If no energy goes to the motor windings, this may indicate a failure.

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11 years 8 months ago #29525807 by neumotiv
Thank you.

re 4 above:. 120 degrees assumes a 2-pole (inrunner) motor, Yes?
You are talking 360/3phases = 120 physical AND \'magnetic\' degrees apart, Yes?

Yet, I am using a 14-pole outrunner motor, so that would be 120 physical degrees divided by 7 di-poles or 17.14 physical degrees apart (equiv to 120 \'magnetic\' degrees apart), Yes?

Also, didn\'t directly answer the question: \"is the Motor Power monitoring actual power being delivered to the motor by the FET output stages(?)\"

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11 years 8 months ago #29525809 by roboteq
120o refers to a single pole motor. If more poles, divide 120 by the number of poles.

The Power Output is the power level that the microcontroller commands the power stage to apply.

This is what you should see at the FET outputs, unless the hall sensor input has an invalid combination (ie all 0 or all 1), of if the power stage is defective.

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