Question : Problem: Interchangeable Battery Chargers

I have a wide array of battery chargers for various devices including cell phones and blue tooth ear pieces.  Do anyone know if these can be interchanged?  Do you have to use the charger that specifically came with your device even if they have the same type of plug?  I have a Motorola ear piece and the back says "input 100-240v - 50/60 hz, and my Blackberry says they same thing.  For outbput the motorola says 5v -- 550mA and the Blackberry says 5vc.c. 0,75A for output.  

Answer : Problem: Interchangeable Battery Chargers

>epoxy on the windings and balancing it first would've helped, I admit

No kidding - an unbalanced motor at high rpms will destroy itself.  Less current just means it probably doesn't reach maximum rpm and self-destruct.  If potentially providing more current was a problem, anyone who installed an expensive high current power supply would regret it, but no one recommends against such a practice - it's the cheapo low end power supplies that cause problems.  A higher current rating does not mean more current is always supplied; it means more is available if needed.

The Motorola and Blackberry use the small trapezoidal connector commonly found on some USB cables, so polarity is not an issue.  It is designed to be hooked up to a PC.