On Tue, 2007-01-23 at 17:19 +1030, Tim wrote: > On Tue, 2007-01-23 at 01:17 -0500, Ric Moore wrote: > > They recommended each machine have it's own line to reduce line noise, > > in the conduit. > > Hmm, it's a crap power supply that doesn't act as an isolation point > between the mains supply and the rig. Mains filtering should stop > interference getting in or out of the device. The regulators should > also go some way to removing any incoming noise. > > > Proper grounding is essential. > > I thought un-earthed equipment was still the norm in the US? Hell no. Code requires earth grounding in residential and especially commercial installations. All power tool type extension cords have grounding prong, unless it's a two wire lamp extension cord or something like that. Utility outlets in houses are required to be grounded and all PSU power cords have a grounding plug. There are alot of power tools that carry a two wire cord, but most of the time they are constructed of non-conductive plastic materials on the outside with the metal parts inside the tool. There are codes regulating their construction as well; if they aren't grounded, they have to meet safety standards for protection without a ground. LX -- °°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°° Off Topic or Political Discussions: http://mandrakeot.mdw1982.com/ http://www.mdw1982.com/mailman/listinfo/mandrakeot "Character is what you do when nobody's looking." - J.C. Watts °°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°