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Unread 06-08-2007, 14:40
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Al Skierkiewicz Al Skierkiewicz is offline
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Re: Consolidating PWM's to one serial cable

Quote:
Originally Posted by Qbranch View Post
also CAT5 normally is single core and because of that it doesnt have a long mechanical life when it comes to bending/vibration, and running a seperate wire for grounding does introduce, again, the possibility for wiring in more noise (every wire is afterall an antenna weather we want it to be or not ).
The correct term is solid wire and you are correct, solid is not a good choice for moving objects as it is prone to fail with repeated vibration. The problem with a single ground is not so much as an antenna as that the noise for each of the signals is added in the common return wire (ground...although not really ground). This is sometimes referred to as "ground loop". In the case of multiple Victors, motor noise will be added as well since there is not a perfect return for motor current to the battery for each branch circuit. Some motor current is bound to flow on the common PWM wire.
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