Gary Hvizdak wrote: > Wed Mar 24 22:14:20 EDT 2010 LS (W5QD) wrote ... > > The mat doesn't have to be grounded ... > > > WARNING! The statement W5QD just posted is completely false! The ESD mat > must be grounded in order for it to be able to dissipate an electrical
The full reply from W5QD was perfectly correct. Everything conductive has to be connected together, but there is no need to connect to the earth itself. In practice, if the soldering station is mains powered, the result will be that it is also connected to the green wire in the mains, although that can be at a significantly different potential than the local true earth. In fact, unless there is a high resistance in the lead to the mat, it can be very dangerous to connect it to true earth, as it is usually possible to touch the connection to the mat and something cannected to the green wire, at the same time. > charge. If you don't ground the mat, then you might as well not have it, > since your entire work area could very easily be floating at tens of > thousands of volts above ground, just waiting for "somewhere" to discharge > "to" and "something" to discharge "through"! That is perfectly acceptable, as long as there is no way of touching something that has a relatively low resistance to true earth. (Incidentally, I have a feeling that true earth isn't actually electrically neutral, something has to balance the charge in thunderclouds. In a practical amateur environment, the optimum ground for this purpose is the green wire, and bringing any other ground into the situation can be dangerous. However, if you have a battery or gas soldering iron, and no conductors which could touch the work, but aren't connected to the mat, there need be no connection at all to anything approximating true earth. The green wire is not a best approximation to true earth for this purpose, it is actually the ideal thing to connect to, even if it bears no resemblance to true earth. -- David Woolley "we do not overly restrict the subject matter on the list, and we encourage postings on a wide range of amateur radio related topics" List Guidelines <http://www.elecraft.com/elecraft_list_guidelines.htm> ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
