Re: Banebots RS-775 Case Short
 

Sorry that I wasn't as clear as possible above; I know BaneBots doesn't make the motors. I was referring to the fact that we call them "BaneBots motors", when we should be calling them "[unknown manufacturer] motors" sold by BaneBots. (In the same vein as "CIM motors" sold by AndyMark, even though they have an AndyMark part number.)

And I'm quite sure they're not (at least not usually) Mabuchis. (I'd described the reasons in another thread, but sufficient to say, they are missing all the distinguishing marks of a Mabuchi product.)

Re: Banebots RS-775 Case Short
 

Don't you just love reigning in the mechanical guys with electrical details? ;)

Seriously though, I think this fact would be sufficiently limiting on CIM usage, as per John's original post suggesting the motors weight and power consumption would help regulate it. I'm all for unlimited CIMs!

Matt

Re: Banebots RS-775 Case Short
 

Well, look at that. The shipment just showed up!

2011 F-P Motors and associated gearboxes and motor-cap products are now available.

Thanks for your patience,
Andy

Re: Banebots RS-775 Case Short
 

Would you please post a link to your list of reasons. Thank you.

Re: Banebots RS-775 Case Short
 

Re: Banebots RS-775 Case Short
 

Someone has to do it and I'm just that guy!

Re: Banebots RS-775 Case Short
 

Also, in his post John did not seem to be implying that motor choice be limited to CIMs, only that # of CIMs be unlimited.

Re: Banebots RS-775 Case Short
 

Thanks Joe. I don't know how I missed that thread.

Re: Banebots RS-775 Case Short
 

follow up RS-775 Banebots motor rotor short to case problem..

inspection results of new packaged Spare Parts this weekend at LA Regional:

The rotor laminated iron core appear to have NO or insufficient insulation
thus enamel windings eventually short against the core at end (edge turn)

GOOD armatures have a brown fiber or cloth insulation (such as CIM's)
to prevent such winding shorts (enameled wire is not good enough alone)

possibly mfr short cut is relying on a substitute insulator such as epoxy varnish etc which fails to provide adequate thickness around lamination edges

End result: if ALL RS-775's were mfrd in this manner
** NONE ** are safe to use on the robot
as they are likely to continue to degrade with use.

first winding to short does not impact motor physical performance
but will not pass chassis isolation requirement
short(s) can occur mid match.

2nd and subsequent shorts to core represent shorted turns.. each decreasing available torque while increasing current draw=declining efficiency

If you plan to keep the RS775's frequently remove two motor spade to controller (Jag or Victor) and do continuity to case test for each RS775.

Note: the isolation continuity test to chassis will read ~2megohms one direction (polarity) and ~300K ohms the opposite (leads swapped) due to the diode path in the controllers even though the motor lead to case short is only an ohm or two!! Note that in this mode if the motor is slightly rotated the polarity detected for min / max swaps!! i.e. alternates.. due to different H-brdige path in the controller..

Someone should disassemble all the smaller Banebots motor types to verify/report here if their rotor lamination's lack proper insulation.. TBD...

I'm unaware of any such failures to date. Perhaps smaller wire diameter does not pose as great a potential enamel break thru as the much larger AWG wire used on the 775 armature's.

Re: Banebots RS-775 Case Short
 

Sounds like a larger radius on the core edges would go a long way toward mitigating this problem?

Re: Banebots RS-775 Case Short
 

So, now it's 2012, and these motors are legal again. Any word on whether the problem has been fixed?

Plus, my memory of all this is a little hazy, does/did this issue extend only to the 18V model, or did it include the 12V model as well?

Re: Banebots RS-775 Case Short
 

Anyone that saw the Einstein finals last year may know why we aren't using bane bots this year.

Re: Banebots RS-775 Case Short
 

Would you mind explaining?

Let's just say 177 and 2016 did very well without us. They say your critical components fail at the worst times and it is most certainly true. Watch the matches.

See http://www.chiefdelphi.com/forums/sh...t=781+Einstein Paragraph 7 for an explanation of our unfortunate luck on Einstein 2011.