[NSRCA-discussion] OS 1100HV ESC catastrophic failure

[Bob Kane]

I had an OS 1100HV ESC burn up in my 73" AJ Laser on Sunday.  The motor is a Hacker A60 V2.  I set it up to use the same batteries and prop as my pattern plane.  The plane is now about 3 years old but had maybe 30 flights on it.
I was performing the current Masters sequence at a club airshow and was just entering the end of box down line 1/2 Square with snap when I noticed my smoke system was on. Luckily I had enough speed and altitude and was able to dead stick land the plane OK.

The ESC was absolutely smoked, it melted the case and blew the heat sink off the components. One of the motor leads was unsoldered. 

It was suggested that a motor lead had shorted causing the failure, but I cannot find any evidence of a shorted lead or connector.  I used a drill to spin the motor and measured exactly the same voltage across all the lead combinations which would rule out a shorted winding.

I am very reluctant to install my precious NIB backup OS controller without some kind of absolute verification that the motor is OK.

Does anyone have any suggestions to prove out the motor?

Thanks.


Bob Kane getterflash at yahoo.com