Hobbyist Forums banner

1 - 17 of 17 Posts

·
Registered
Joined
·
5 Posts
Discussion Starter #1
Can some one please explain the differance between sensored and sensorless brushless motors. Is sensored better?
 

·
Registered
Joined
·
7,343 Posts
VicnPA

A couple weeks ago, I was at my Local Hobby Shop and a guy came in with a new car he bought with a Sensorless Motor/Esc combo.

I don't recall the brand, but the ESC looked like the Speed Passion LPF, but it was sensorless.

He was having a problem with the ESC setup - (so he thought) It had Forward and Reverse...but if the car went forward, it didn't want to back up...if it went backward, it didn't want to go FORWARD, if he STOPPED while going in those directions.

He had to switch directions while the car was moving...

In RACING, guys have found many times a SENSORLESS Motor won't take OFF on the line, so they get RUN OVER. The car works fine with a shove to get the car moving.

This seems to come from the sensorless motor being shoved backward prior to the start of the race - and the motor doesn't know what to do when you hit the throttle.

YOU DON'T HAVE THAT PROBLEM generally WITH SENSOR BASED Brushless Motors.
 

·
Registered
Joined
·
5,420 Posts
VicnPA

A couple weeks ago, I was at my Local Hobby Shop and a guy came in with a new car he bought with a Sensorless Motor/Esc combo.

I don't recall the brand, but the ESC looked like the Speed Passion LPF, but it was sensorless.

He was having a problem with the ESC setup - (so he thought) It had Forward and Reverse...but if the car went forward, it didn't want to back up...if it went backward, it didn't want to go FORWARD, if he STOPPED while going in those directions.

He had to switch directions while the car was moving...

In RACING, guys have found many times a SENSORLESS Motor won't take OFF on the line, so they get RUN OVER. The car works fine with a shove to get the car moving.

This seems to come from the sensorless motor being shoved backward prior to the start of the race - and the motor doesn't know what to do when you hit the throttle.

YOU DON'T HAVE THAT PROBLEM generally WITH SENSOR BASED Brushless Motors.
That problem is more prevalent with direct drive cars. I have never had that happen with my electric 1/8th scale Losi with a [original] Mamba Max driving a Neu motor. Or with a Castle Sidewinder driving a Novak 8.5 (without the sensors) in my XXX-T (offroad truck). The slack in the drivetrain/cvds lets the controller sync up with the motor instantly.
 

·
Registered
Joined
·
214 Posts
Get sensored period. Sensorless will work OK with about 8.5 turn or under. I have seen guys that said they have no problems with sensorless doing the finger ballet after a wreck or rolling backwards trying to get started again while the field of cars passing them. Just for giggles I tried sensorless in 13.5 sprint car and got run over at the start of the race everytime. Get in an accident and the turn marshalls thought I was broke. Once up to speed I had no problems and incedents rolling forward were no issue. Don't even think about sensorless 21.5 or 17.5...........terrible...........
 

·
Registered
Joined
·
641 Posts
sensored vs. sensorless
sensored mainly centers motor in forward position.
sensorless has a tendecy to shuffle back
sensorless will give your greater power
depends on useage
 

·
Registered
Joined
·
1,813 Posts
Get sensored period. Sensorless will work OK with about 8.5 turn or under. Don't even think about sensorless 21.5 or 17.5...........terrible...........
Now that all depends on the controller:thumbsup:I can run a sensored or sensorless 17.5 behind my hobby wing 35 a esc with no issues(off-road),But a race buddy of mine tried the same thing with a castle speedo and got horrible cogging on the higher wind motors (13.5,17.5). So, like sensored speedo's, the firmware and adjustability DO matter.
 

·
Graphics Specialist
Joined
·
4,556 Posts
castle has some features that you can adjust that will eliminate the cogging. I had some cogging in my 1/18th mamba 25 with a 6800, adjusted the start power and a couple of other things and had no probs after that
 

·
Registered
Joined
·
525 Posts
sensor wire broke on my 13.5 novak ss running on tekin rs pro at the us open wheel. didnt seem much faster at all when it did move. and whenever i hit brake to stop for accident infront of me or if stopped it would cog and then go backwards a bit then it would decide to go forward eventually after some time of cogging
 

·
Registered
Joined
·
1,306 Posts
Unfortunately I had a similar issue this past Friday. I run a Mamba Max Pro 1 cell with a motor running a sensor wire. During the main with 30 seconds left, my sensor wire came loose and fell out of the esc. It was like someone threw my car into neutral. I had nothing. :( I tried to get the car to go and it just skipped a long. I was bummed but nothing I could do.
 

·
Registered
Joined
·
214 Posts
As long as the sensor wire does not fall off, the sensored will be almost 100% reliable in forward, reverse and race starts. I will challange any bozo that says there castle 5700kv is no problem in a race. Plus the fact that most are not legal to run in standard classes like 10.5 or 13.5.
 

·
Registered
Joined
·
321 Posts
will after reading the write up on novaks site .. ill stay with sensor .. we do have a guy who runs a mamba sensorless motor at our track 5700 i think to and he takes off just fine from start .. i dont rememeber the ESC tho he uses ..

i guess this boils down to what you like and dont like ..
to me if your ESC knows what the motor is doin at all times is best .. kind of like a hubby n wife .. they talk they work good togther "so i been told" lol .... they dont talk omg get the fryin pan out lol or rollin pin your choice there lol
 

·
Registered
Joined
·
214 Posts
Well next time your at the track. Just watch the guys car with the 5700kv mamba. Watch the sometimes long pauses after a collision or backed into a corner. It doesn't happen all the time, but enough to be a problem. I have the castle and losi sensorless (more than one in each) and they are not 100% reliable in racing....
 
1 - 17 of 17 Posts
Top