MOTOR ROTATION
05-08-2011 | 02:44 PM
#1
MOTOR ROTATION
I have a Viper VST sensored brushless motor and a sensorless esc. for some reason the motor won't turn the trans forward. I can't change the motor rotation on the esc, but the directions on the esc say that you can move two of the three wires to change the rotation. Now, Viper says not to mess with the ABC order of the wires because it will damage the motor system.
My question is if the motor is sensored and the esc is not, can you change the wires to change the rotation with no damage to the system?
My question is if the motor is sensored and the esc is not, can you change the wires to change the rotation with no damage to the system?
05-08-2011 | 03:00 PM
#2
Tech Master
iTrader: (3)
Joined: Jul 2008
Posts: 1,465
From: Melbourne, Australia
Why are you running a sensored motor on a sensorless ESC ?
If you are running it without the sensor wire then you are turning it into a sensorless motor
Swapping any two motor wires will change the rotation direction
Cheers
If you are running it without the sensor wire then you are turning it into a sensorless motor
Swapping any two motor wires will change the rotation direction
Cheers
05-08-2011 | 04:11 PM
#3
Joined: Apr 2009
Posts: 3,055
You are almost turning it into a sensorless motor, there are still a few differences you should be cautious of.
First, sensored motors are usually wye wound, while most sensorless are delta wound. A wye type motor, of relatively high resistance (lower Kv), will not normally exhibit good startup quality on a sensorless controller. I think most people like myself have decided that anything slower than a 10.5 is not a good match with a sensorless controller. However......
Secondly, sensored motors come with increased timing on the motor, while sensorless type motors usually will be fixed at zero timing, as it is controlled thru the ESC. Luckily, Viper was honest and smart in choosing to have the timing value listed on the can as the actual amount. Some manufacturers build a certain amount into the windings, then add additional timing into the adjustment. I am not sure if it is true or not, but I read that Novak motors have 30* built into the motor, meaning that when you have the value on the can at zero, you are actually getting 30* already, with no choice to turn it down. Compared to a zero degree sensorless motor, any sensored type motor is going to have a significant amount of increased timing, and this can also lead to poor startup quality or even motor failure in extreme cases.
Knowing this, I would make sure to set the motor timing as low as possible. The marks go down to 15* on the Viper, and I would probably try to go a little lower than that within reason. And if you have something like a 17.5 or even 13.5, I would not expect super smooth starts, but it should run just fine once up to speed. Dont forget that ESC settings like start power or timing can also improve or worsen your low speed operation, so dont be afraid to try them if you need to change anything. So to answer your question, I dont see any reason not to switch any two wires like you would with a sensorless motor. The sensors require the ABC orientation and can cause serious problems when it is not correct, but without them it is essentially like a sensorless motor, as the previous reply stated.
First, sensored motors are usually wye wound, while most sensorless are delta wound. A wye type motor, of relatively high resistance (lower Kv), will not normally exhibit good startup quality on a sensorless controller. I think most people like myself have decided that anything slower than a 10.5 is not a good match with a sensorless controller. However......
Secondly, sensored motors come with increased timing on the motor, while sensorless type motors usually will be fixed at zero timing, as it is controlled thru the ESC. Luckily, Viper was honest and smart in choosing to have the timing value listed on the can as the actual amount. Some manufacturers build a certain amount into the windings, then add additional timing into the adjustment. I am not sure if it is true or not, but I read that Novak motors have 30* built into the motor, meaning that when you have the value on the can at zero, you are actually getting 30* already, with no choice to turn it down. Compared to a zero degree sensorless motor, any sensored type motor is going to have a significant amount of increased timing, and this can also lead to poor startup quality or even motor failure in extreme cases.
Knowing this, I would make sure to set the motor timing as low as possible. The marks go down to 15* on the Viper, and I would probably try to go a little lower than that within reason. And if you have something like a 17.5 or even 13.5, I would not expect super smooth starts, but it should run just fine once up to speed. Dont forget that ESC settings like start power or timing can also improve or worsen your low speed operation, so dont be afraid to try them if you need to change anything. So to answer your question, I dont see any reason not to switch any two wires like you would with a sensorless motor. The sensors require the ABC orientation and can cause serious problems when it is not correct, but without them it is essentially like a sensorless motor, as the previous reply stated.
05-08-2011 | 05:08 PM
#4
Thanks for the input guys, found the problem. I think when I changed out motors it messed with the esc somehow. the motor works fine now that I reset the radio to the esc.
And the reason that I am running a sensorless esc with the Viper is because I bought the esc first, not knowing that most of the good motors are sensored. I plan to get another speedo fairly soon, I'm fairly new to the brushless setup and I'm still learning.
I tested the system and there are no issues. the motor did come with 30 deg timing so I set the esc at zero to be safe. the esc is a 60 amp and I'm running an 8.5, This is my SC 2wd setup. I was thinking of backing the timing down to get some of those rpm's down.
And the reason that I am running a sensorless esc with the Viper is because I bought the esc first, not knowing that most of the good motors are sensored. I plan to get another speedo fairly soon, I'm fairly new to the brushless setup and I'm still learning.
I tested the system and there are no issues. the motor did come with 30 deg timing so I set the esc at zero to be safe. the esc is a 60 amp and I'm running an 8.5, This is my SC 2wd setup. I was thinking of backing the timing down to get some of those rpm's down.
05-08-2011 | 06:26 PM
#5
Tech Champion
Joined: Oct 2007
Posts: 7,341
You are almost turning it into a sensorless motor, there are still a few differences you should be cautious of.
First, sensored motors are usually wye wound, while most sensorless are delta wound. A wye type motor, of relatively high resistance (lower Kv), will not normally exhibit good startup quality on a sensorless controller. I think most people like myself have decided that anything slower than a 10.5 is not a good match with a sensorless controller. However......
Secondly, sensored motors come with increased timing on the motor, while sensorless type motors usually will be fixed at zero timing, as it is controlled thru the ESC. Luckily, Viper was honest and smart in choosing to have the timing value listed on the can as the actual amount. Some manufacturers build a certain amount into the windings, then add additional timing into the adjustment. I am not sure if it is true or not, but I read that Novak motors have 30* built into the motor, meaning that when you have the value on the can at zero, you are actually getting 30* already, with no choice to turn it down. Compared to a zero degree sensorless motor, any sensored type motor is going to have a significant amount of increased timing, and this can also lead to poor startup quality or even motor failure in extreme cases.
Knowing this, I would make sure to set the motor timing as low as possible. The marks go down to 15* on the Viper, and I would probably try to go a little lower than that within reason. And if you have something like a 17.5 or even 13.5, I would not expect super smooth starts, but it should run just fine once up to speed. Dont forget that ESC settings like start power or timing can also improve or worsen your low speed operation, so dont be afraid to try them if you need to change anything. So to answer your question, I dont see any reason not to switch any two wires like you would with a sensorless motor. The sensors require the ABC orientation and can cause serious problems when it is not correct, but without them it is essentially like a sensorless motor, as the previous reply stated.
First, sensored motors are usually wye wound, while most sensorless are delta wound. A wye type motor, of relatively high resistance (lower Kv), will not normally exhibit good startup quality on a sensorless controller. I think most people like myself have decided that anything slower than a 10.5 is not a good match with a sensorless controller. However......
Secondly, sensored motors come with increased timing on the motor, while sensorless type motors usually will be fixed at zero timing, as it is controlled thru the ESC. Luckily, Viper was honest and smart in choosing to have the timing value listed on the can as the actual amount. Some manufacturers build a certain amount into the windings, then add additional timing into the adjustment. I am not sure if it is true or not, but I read that Novak motors have 30* built into the motor, meaning that when you have the value on the can at zero, you are actually getting 30* already, with no choice to turn it down. Compared to a zero degree sensorless motor, any sensored type motor is going to have a significant amount of increased timing, and this can also lead to poor startup quality or even motor failure in extreme cases.
Knowing this, I would make sure to set the motor timing as low as possible. The marks go down to 15* on the Viper, and I would probably try to go a little lower than that within reason. And if you have something like a 17.5 or even 13.5, I would not expect super smooth starts, but it should run just fine once up to speed. Dont forget that ESC settings like start power or timing can also improve or worsen your low speed operation, so dont be afraid to try them if you need to change anything. So to answer your question, I dont see any reason not to switch any two wires like you would with a sensorless motor. The sensors require the ABC orientation and can cause serious problems when it is not correct, but without them it is essentially like a sensorless motor, as the previous reply stated.
05-09-2011 | 08:02 AM
#7
Joined: Apr 2009
Posts: 3,055
Right on guys, re-reading my post I see it was clearly wrong on a few points about the timing
, I need to smoke some more of that stuff I guess. However, I do stand that it is not quite the same as a typical sensorless motor just because the sensors are unplugged.
, I need to smoke some more of that stuff I guess. However, I do stand that it is not quite the same as a typical sensorless motor just because the sensors are unplugged.
.
05-09-2011 | 01:57 PM
#9
Tech Champion
Joined: Oct 2007
Posts: 7,341
Cheers guys
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