Motor test results after tipover. Are these figures normal?

...... I just have one follow on question if I may:

Can someone please clarify for me (if possible) what the normal value ranges should be? I wasn't entirely clear on what those should be.
.....
I'm not sure how to answer this. Unless something is really wrong the commanded and actual speed values will always be "normal". I.e. Once commanded the ESC will do what's necessary to achieve that speed so both these values are "normal".

However, the load value may be abnormal. An obstructed motor, impaired bearings, etc. will cause a higher than normal load value. I suspect that the load value is actually a current measurement. Although I've looked at several lost or broken prop incidents I haven't thought about what a normal load value is.

If you're interested you might want to perform a set of baseline measurements and then re-measure at certain intervals. Maybe with and without props.
 
I'm not sure how to answer this. Unless something is really wrong the commanded and actual speed values will always be "normal". I.e. Once commanded the ESC will do what's necessary to achieve that speed so both these values are "normal".

However, the load value may be abnormal. An obstructed motor, impaired bearings, etc. will cause a higher than normal load value. I suspect that the load value is actually a current measurement. Although I've looked at several lost or broken prop incidents I haven't thought about what a normal load value is.

If you're interested you might want to perform a set of baseline measurements and then re-measure at certain intervals. Maybe with and without props.

Hi Bud. Thanks for the response. I think I phrased my question poorly but the info in your response has also made me realize the naiveté of my frame of mind at the time I wrote my post. Obviously, "normal" is a relative term and not very specific. My question related to typical values when a P3 is powered up on the ground with props. I figured I'd probably see a deviation from typical (or expected) values during the power up test if one or more of the motors was obstructed or otherwise not operating as it should.

However, if I understand you correctly, what I'm looking for are deviations between the commanded and load value? Specifically, I'm looking for a load value that is higher than the commanded value. The question is (having never really seen these values before) if there is something that could be used as a reference. For example, something that would tell me that commanded value = 1, actual = 1.1, load = 3.8 is "OK" but commanded value = 1, actual = 1.1, load = 3.9 is "BAD". If so, then I can do a series of A/B tests as you suggested and analyze the delta between those two values in order to determine if one motor is potentially the root cause of my issue.

Not sure if that helped or not but I sincerely appreciate your help.

Rob
 
Hi Bud. Thanks for the response. I think I phrased my question poorly but the info in your response has also made me realize the naiveté of my frame of mind at the time I wrote my post. Obviously, "normal" is a relative term and not very specific. My question related to typical values when a P3 is powered up on the ground with props. I figured I'd probably see a deviation from typical (or expected) values during the power up test if one or more of the motors was obstructed or otherwise not operating as it should.

However, if I understand you correctly, what I'm looking for are deviations between the commanded and load value? Specifically, I'm looking for a load value that is higher than the commanded value. The question is (having never really seen these values before) if there is something that could be used as a reference. For example, something that would tell me that commanded value = 1, actual = 1.1, load = 3.8 is "OK" but commanded value = 1, actual = 1.1, load = 3.9 is "BAD". If so, then I can do a series of A/B tests as you suggested and analyze the delta between those two values in order to determine if one motor is potentially the root cause of my issue.

Not sure if that helped or not but I sincerely appreciate your help.

Rob
It seems that the P3 does a pretty good job of determining if there is an ESC issue during the motorStart 2 burst sequence. If there is something wrong the P3 stops the motors and issues an ESC error. I was assuming you were trying to monitor motor health to catch an issue before it turned ugly.

I think I understand your question and what you're trying to determine. Unfortunately, the answer isn't as straightforward as it should be.There is a lot that isn't known about these values. What is known came from reverse engineering and experiments. Only DJI engineering knows the real story and they aren't sharing. We don't know the units or range for the load field, only that it's related to mechanical resistance. I mentioned that I suspect it's a measure of motor current. You might want to check out this which was done by @Luap to help determine what is known about the load field.

Given the lack of quantitative information the only method that I can see working is to compare the load values against themselves. E.g., for a given speed if two motors show a different load that would indicate a problem. Similarly, for a given motor and speed if the load value changes as the motor ages that could indicate a problem.
 
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Hi Bud. Thank you again for the response as well as the link to @Luap's vid. The weather has finally turned for the better here so I'm going to take the P3 up for the first time in a couple of weeks. Sincerely appreciate the info and will post if I find anything that I think might be of value.

Cheers, mate.

Rob
 

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