Thread: chassis isolation, contrary to UL1740?
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Unread 16-10-2008, 08:42
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Re: chassis isolation, contrary to UL1740?
Good points all, and yes, the UL1740 spec was written more with AC powered robots in mind (automated welders and the like) but does still apply explicitly to "mobile robots". I know at least on the robot that we have docking to our 1740 dock the negative terminal of the battery is connected to chassis for two reasons, EMI compliance as well as fault return path (for popping fuses). From my own oppinion, I'd rather have a loose wire hit the chassis, pop a breaker or fuse and be a dead wire before it hits an IC on one of my pc boards... This is, of course, on a completely enclosed robot, where the only shock a human can really get is an ESD one (a reasonably nasty one at that). The FIRST robots, being open framed certainly do present a different situation, and you're starting to sell me on the isolation...

It would be neat to hear an expert from UL chime in on this...
Thanx for the responses!