In that case, please try to use around 11-11.1 V as input voltage. I had some older OpenRB-150 that would not work at 12V but worked OK at 11V. But supposedly that issue is resolved by Robotis by now.
Some more details in this older posting
In that case, please try to use around 11-11.1 V as input voltage. I had some older OpenRB-150 that would not work at 12V but worked OK at 11V. But supposedly that issue is resolved by Robotis by now.
Some more details in this older posting