The NEC (National Electric Code) doesn't normally allow soldering for power connections. My guess is that they are concerned that a high current fault (short) could melt the solder.
Jim Nichol On Feb 16, 2012, at 9:58 PM, Philip Carli wrote: > Would soldering the green wire to the case do as well as a screw? I believe > the case is pot metal and tapping it for a screw might shatter the whole > thing. Philip Carli > ________________________________________ > From: phono-l-boun...@oldcrank.org [phono-l-boun...@oldcrank.org] on behalf > of Greg Bogantz [gbogan...@charter.net] > Sent: Thursday, February 16, 2012 8:27 PM > To: Antique Phonograph List > Subject: Re: [Phono-L] Does anyone know how to make a Jones Motrola _safe_? > > I believe the Motrola has a metal case. The danger can occur if there > is electrical leakage from the internal wiring to the case and its attached > metal parts which can occur due to carbonized insulation that can begin to > develop a lower resistance. I would recommend first testing with an > ohmmeter to determine if there is already leakage from either of the wires > leading from the motor to the case. An ohmmeter reading should indicate a > very high or infinite resistance from either wire to the case when things > are correct. If you measure any significantly lower resistance, the > internal wiring will need to be redone or repaired. If there is good > isolation from the motor wires to the case, I would recommend replacing the > line cord with a modern three-wire cord with a 3-terminal AC plug. Connect > the black and white wires to the motor circuit as was done in the original > 2-wire cord. Then connect the green wire to a screw on the metal case. > This will privide a grounding connection from the case to your household > earthing system. If electrical leakage should develop in the future, it > will be routed thru the green wire to your household ground system (assuming > you plug the cord into a modern 3-wire outlet). In the worst case, it will > blow a fuse or circuit breaker rather than leaving the system a shock > hazard. > > Greg Bogantz > > > > ----- Original Message ----- > From: "Philip Carli" <philip_ca...@pittsford.monroe.edu> > To: "Antique Phonograph List" <phono-l@oldcrank.org> > Sent: Thursday, February 16, 2012 7:08 PM > Subject: [Phono-L] Does anyone know how to make a Jones Motrola _safe_? > > >> >> I have a Jones Motrola I'm trying to rewire, but I read that they can be >> dangerous in their original ungrounded state? Any ideas on how I can deal >> with this? Any help would be appreciated. Thanks, Philip Carli >> >> ________________________________ >> >> This email message and any attachments may contain confidential >> information. If you are not the intended recipient, you are prohibited >> from using the information in any way, including but not limited to >> disclosure of, copying, forwarding or acting in reliance on the contents. >> If you have received this email by error, please immediately notify me by >> return email and delete it from your email system. Thank you. >> _______________________________________________ >> Phono-L mailing list >> http://phono-l.org > > _______________________________________________ > Phono-L mailing list > http://phono-l.org > > ________________________________ > > This email message and any attachments may contain confidential information. > If you are not the intended recipient, you are prohibited from using the > information in any way, including but not limited to disclosure of, copying, > forwarding or acting in reliance on the contents. If you have received this > email by error, please immediately notify me by return email and delete it > from your email system. Thank you. > _______________________________________________ > Phono-L mailing list > http://phono-l.org _______________________________________________ Phono-L mailing list http://phono-l.org
