Damaged T100: problem with motor's stator

Hi,

I have recently bought a T100. Unfortunately, with just a few minutes of run time underwater, the thruster stopped rotating. The blades were hard to rotate manually, which made me think that there was something stuck in the rotor.

When I disassembled the motor, I was shocked to find that the stator axis was bent and it was scrapping the inner diameter of the rotor (see attached image). I could not believe how it got bent so easily without much usage.

Can y0u please explain why this may have happened, so that we could avoid this in the future. Also, will there be any possibility of replacement or a repair to make it working again.

Santhosh



@Santhosh R,

Did you run the Thruster for any length of time out of the water before putting it in the water?

BR recommends to not run the Thrusters out of the water for more than 30 seconds.

Regards,

TCIII AVD

Hi Santhosh,

We’ve seen this a few times - it’s almost always due to the thruster overheating to a extreme that melts the plastic. That can happen if a motor phase is shorted to the power supply, if jammed and running at very high current, or if run in air for extended periods. Do you think any of these things might have happened?

-Rusty

I had exactly the same problem happened today at the river, two T100 were going flat out in the water to keep up with river flow of 1.2m/s then after 15min one thruster stopped and I lost control over boat , luckily it was just a few meters away from me so I got it before it took off down the stream ( 30k of equipment on it ) , at the work shop I found exactly the same problem, it looked like the coating have melted and started to bubble then jammed the rotor consequently bending the stator,
does BR thrusters limited to how long they can operate at full throttle at one time?

@fardman,
Could there have been the possibility of a temporary jam of the impeller due to river water weeds/sediment?
Regards,
TCIII AVD

Hi IP68,

A temporary jam is a possibility, this could have put undue load on the thruster and caused it to overheat. The T100 thruster is not optimized for long term high throttle use in a potentially debris filled environment, rather it is intended for use on ROVs and other vehicles where full throttle occurs in short bursts, or long term lower throttle. We are working on an update to the T100 design which will address this issue. The T200 is a more appropriate thruster for long term high throttle use, and was designed with this in mind.

Send us an email at support@bluerobotics.com and we’ll get this issue fixed!

-Adam

Hi All ,
Thanks for you input guys,
Everything possible but I haven’t found any debris or sea weed inside the motor when opened it ,

Adam
That’s good to know, I’m thinking of buying T200 for a long time now, but I’m waiting for blue ESC version to come out , is it anywhere near final roll out ?

Cheers

IP68,

The revised BlueESC should be available around March.

-Adam

Hello all,

I do not remember running it in air for long periods of time or even 30 seconds. I am still unsure about the actual cause of this problem, but yeah, could be an overheating problem. Also, I learn that T100 is not ideal for long runs at full throttle - seems like an important note to all users.

I apologise for my delayed response; I have been busy for the last few weeks.

Hi Santhosh,

Send us an email at support@bluerobotics.com and we’ll get this issue fixed!

-Adam