Locked Re: HT-37 transformer failure due to rapid STBY-->OFF-->STBY
¿ªÔÆÌåÓýOoops ?sorry that was a copy of Jims post enlarged so I could read it I will delete it on line later Jim if you are going to measure the volts or amps , you need a meter and two leads, and then the leads somehow go to the core, and perhaps it is a whole turn, then you cut it to a half turn, and ? ?and 1/8 th turn, and then a 0.00005 turn and finally no turn, I¡¯ll bet your meter reads the same. In the final test the leads go around the core and join and the meter leads become the whole turn. ??I don¡¯t think that was apparent when ?? did his first experiments but ?´¡³¾±è¨¨°ù±ð ??or Faraday spoke about the closed loops. ? You can make a super micro-mini- meter anf put it right at your half turn, but to get any volts they have to extend ?the two ? turn leads around the core to reach your half turn, and that makes one whole conductive turn. ?I have never been able to walk up half-a-step either.. frustrating stuff If you don¡¯t finish the turn the laws mean nothing, ? From: [email protected] [mailto:[email protected]] On Behalf Of Jim Whartenby via groups.io
Sent: Sunday, August 11, 2024 7:34 PM To: [email protected] Subject: Re: [HallicraftersRadios] HT-37 transformer failure due to rapid STBY-->OFF-->STBY ? Don In a transformer, a half turn starts on one side of the laminated core and exits on the other.? Since the Weller has that plated copper tube entering the core on one side and exiting the core on the other, it is by definition, a half turn.? It does not matter if the tube wraps around the outside of the lamination, it is still a half turn through the core.? If a winding makes one full wrap around the core that holds the primary and exits on the same side that it entered, then it is a full turn.? If you measure the open circuit voltage of the Weller soldering gun tube, it should be approximately a quarter volt.? That tube allows about 100 VA to be transformed to about 400 amps @ 0.25 volt! ? As long as you can fit an insulated wire between the bobbin and the laminations and make a full turn as in above then you can determine the turns-per-volt of any power?transformer.? I prefer 10 turns, make the measurement and then divide it by 10 but you can do as you like.? You must have a transformer or two in your junk-box so it should be easy to verify this procedure. ? Typically one strips off only the secondary windings and keeps the primary intact.? Knowing the voltage produced by a high current heater winding and counting the turns will give the same result for the turns-per-volt of that particular transformer.? Then wind as many turns as needed to get the output voltage wanted in the secondary windings.? This was one of the first lab experiments in college for transformers in AC circuits. Regards, Jim -- don??? va3drl |
don Root