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A-B-C to C-B-A phase crossing

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A-B-C to C-B-A phase crossing

Old 12-02-2019, 06:21 AM
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Default A-B-C to C-B-A phase crossing



Hi guys, I've got a technical question: due to clean cable routing, I had to cross the phases from the esc to motor.
From esc phase A the wire went to motor phase C, B went to B, and C went to A. At the same time I crossed the wires in the sensor cable following the same logic.

Can you please explain me why the motor didn't work in such configuration? Isn't the same for the esc logic? Just the rotation would be inverted... I think...

I attach a picture, which is not mine, to explain the problem of cable routing I would like to avoid

*** to be more clear the picture refers to normal phase connection. Inverting the phases would allow the wires to run straight
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Old 12-02-2019, 06:53 AM
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Originally Posted by Flygio View Post


Hi guys, I've got a technical question: due to clean cable routing, I had to cross the phases from the esc to motor.
From esc phase A the wire went to motor phase C, B went to B, and C went to A. At the same time I crossed the wires in the sensor cable following the same logic.

Can you please explain me why the motor didn't work in such configuration? Isn't the same for the esc logic? Just the rotation would be inverted... I think...

I attach a picture, which is not mine, to explain the problem of cable routing I would like to avoid

*** to be more clear the picture refers to normal phase connection. Inverting the phases would allow the wires to run straight
Without seeing your handiwork the first suggestion would be that you wired the sensor cable incorrectly. But even if you got it working, this is a terrible idea. The motor wouldn't run properly due to the timing advance now being in the wrong direction, plus the vehicle will be driving the wrong way.

The latest R1/Graupner ESCs will let you swap the order of ABC to CBA with a firmware setting, but otherwise swapping the wire order on sensored motors is unsupported.
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Old 12-02-2019, 08:05 AM
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I have several Orca ESC (B32, R32) and they can be switched using the program card. I suggest that you try that first.
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Old 12-02-2019, 10:26 AM
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You switched 2 wired, the motor will run in reverse and the sensors will then give a bad timing.
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Old 12-02-2019, 11:04 AM
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That picture looks like a HW ESC with an orca fan.
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Old 12-02-2019, 12:28 PM
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Originally Posted by malkiy View Post
That picture looks like a HW ESC with an orca fan.
You're right! After taking a closer look, it looks like my old HW 3.1. I automatically assumed that it was an Orca lol. My apologies for the confusion .
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Old 12-02-2019, 02:46 PM
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Originally Posted by Roelof View Post
You switched 2 wired, the motor will run in reverse and the sensors will then give a bad timing.
Why? You can chose the run direction regardlessly of the timing, the software will reverse it for you
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Old 12-02-2019, 02:47 PM
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Originally Posted by malkiy View Post
That picture looks like a HW ESC with an orca fan.
that pic is not mine, but the concept is the same I'm expressing
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Old 12-02-2019, 02:50 PM
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Originally Posted by gigaplex View Post
Without seeing your handiwork the first suggestion would be that you wired the sensor cable incorrectly. But even if you got it working, this is a terrible idea. The motor wouldn't run properly due to the timing advance now being in the wrong direction, plus the vehicle will be driving the wrong way.

The latest R1/Graupner ESCs will let you swap the order of ABC to CBA with a firmware setting, but otherwise swapping the wire order on sensored motors is unsupported.
That's what I'm not understanding. Why can't it run correctly if I also cross the sensor cable? How is the esc supposed to understand that? The esc should be tricked with the sensor cable crossed....
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Old 12-02-2019, 03:29 PM
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Originally Posted by Flygio View Post
That's what I'm not understanding. Why can't it run correctly if I also cross the sensor cable? How is the esc supposed to understand that? The esc should be tricked with the sensor cable crossed....
The sensor board is rotated a certain number of degrees to advance the timing. The direction it is rotated is important, if you reverse the motor it'll be moving the timing in the opposite direction. Swapping the sensor wire around would only give the same result if there was zero timing on the motor.
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Old 12-02-2019, 03:56 PM
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Consider longer wires. A nice clean arc, or moving further away from the motor by switching it's position with the Rx or something. Short wires can tug on boards.
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Old 12-02-2019, 03:59 PM
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Originally Posted by gigaplex View Post
The sensor board is rotated a certain number of degrees to advance the timing. The direction it is rotated is important, if you reverse the motor it'll be moving the timing in the opposite direction. Swapping the sensor wire around would only give the same result if there was zero timing on the motor.
but normally you can chose to run the motor CW or CCW... the sensor board is just that, sensors... if you set let's say 40 of mechanical timing the esc will then sum or subtract that amount accordingly to the sense of rotation previously declared in the settings... at least I understood it worked like that
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Old 12-02-2019, 04:01 PM
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Originally Posted by Zerodefect View Post
Consider longer wires. A nice clean arc, or moving further away from the motor by switching it's position with the Rx or something. Short wires can tug on boards.
the application I'm asking all this for is a pan car 235mm where the esc and motor will be mounted both on the rear pod, mounted back to back. So wires must be short and straight to do a clean job.
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Old 12-02-2019, 04:59 PM
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Originally Posted by Flygio View Post
but normally you can chose to run the motor CW or CCW... the sensor board is just that, sensors... if you set let's say 40 of mechanical timing the esc will then sum or subtract that amount accordingly to the sense of rotation previously declared in the settings... at least I understood it worked like that
The ESC doesn't know how much mechanical timing the motor has so it can't do any subtraction.
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Old 12-02-2019, 08:54 PM
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Actually the ESC would have to add a lot of advance. You didn't mention what motor you have. But let's assume the minimum mechanical timing on the motor is 30 degrees. Running in reverse that's now 30 degrees of retardation not advance. So if you wanted 40 or 50 degrees of total advance, the ESC would have to add 70-80 degrees. I'm not aware of any ESC that will provide that much because it's completely outside the bounds of "normal".

You might be able to modify your sensor board to physically rotate it in the other direction, which when you're running in reverse would be adding advance. Some sensor boards just have tabs that control the range.

But, you'd be much better off finding an ESC that has the ABC posts in CBA order. My Tekin RS's have the C on the left which would make it really easy to wire as you want.
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