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Janis
03-03-2013, 03:11 PM
Hi,
I could not find any information on max current standard dynamixel cable is designed to handle.
The same for the connectors.
Maybe someone here can help?

Thanks,
Janis.

tician
03-03-2013, 03:56 PM
The pcb connectors are Molex, Inc. Spox 5267 shrouded headers (or equivalent - Robotis sources some parts, like their battery connectors, from a Korean manufacturer and one of the connectors they produce is essentially the same) rated at 3A-250V. The wire is usually 20~22AWG silicone or vinyl insulated wire, with 7~11A being the maximum recommended chassis wiring current (less for long distance power transmission).

Janis
03-03-2013, 04:32 PM
Thanks for the answer.
That is very interesting. 106 and 64 servos are said to draw 5.2A max current and they come with 3A connectors.
And if they are to be wired serially then it means no more than 2 per cable.
Fortunately, the 4 ex106s in my setup are underloaded and do not draw more than 3A altogether.

jwatte
03-03-2013, 07:38 PM
I hope you're not continually stalling the servos, else you'll be seeing overheating of the servos themselves before you see overheating of the cable!
The ratings for the tables and connectors are almost entirely based on heating based on the contact resistance and inherent metal resistance. If your load has any kind of duty cycle, then the amperage will average out (or, rather, the heat will average out) and drawing temporary spikes well above the rated currents will work fine.
The main problem you may see is that high resistance cabling and connectors will drop voltage at high currents, so you may get less oomph than you expect out of a servo on the end of a long chain.