Forums

Data over battery line

Started by Marco Trapanese February 7, 2012
On 2012-02-09, Jan Panteltje <pNaonStpealmtje@yahoo.com> wrote:
> On a sunny day (Fri, 10 Feb 2012 00:02:53 +1100) it happened Grant ><omg@grrr.id.au> wrote in <tug7j7dnvjlj5sf5kcqllu4h4j293v42at@4ax.com>: > >>On Thu, 09 Feb 2012 10:31:41 GMT, Jan Panteltje <pNaonStpealmtje@yahoo.com> wrote: >> >>>On a sunny day (Thu, 09 Feb 2012 19:23:37 +1100) it happened Grant >>><omg@grrr.id.au> wrote in <n407j7lfbg9bes8dvd5gcse7e46c68lpk4@4ax.com>: >>> >>>>Maybe? Technique I used basically shorted the battery for a very >>>>short time, >>> >>>Seems like amateur crap to me. >>>Shorting a battery. >> >>Company got a patent on the technique, so it must've been bad ;) >> >>Grant. > > There have been patents issued on perpetual motion machines. > > You would not want to 'short' the sort of batteries I have been around, > size of a room, the switch and wiring would evaporate immediately. > 1 uS would be far too long,
assuming 6.3kg of copper wiring it's about 30Mj to vaporise it, giving your batteries a peak power ofOVER 30TW, impressive. How did they get the inductance so low on a battery that size? -- &#9858;&#9859; 100% natural
On a sunny day (10 Feb 2012 19:56:32 GMT) it happened Jasen Betts
<jasen@xnet.co.nz> wrote in <jh3spg$3du$1@reversiblemaps.ath.cx>:

>On 2012-02-09, Jan Panteltje <pNaonStpealmtje@yahoo.com> wrote: >> On a sunny day (Fri, 10 Feb 2012 00:02:53 +1100) it happened Grant >><omg@grrr.id.au> wrote in <tug7j7dnvjlj5sf5kcqllu4h4j293v42at@4ax.com>: >> >>>On Thu, 09 Feb 2012 10:31:41 GMT, Jan Panteltje <pNaonStpealmtje@yahoo.com> wrote: >>> >>>>On a sunny day (Thu, 09 Feb 2012 19:23:37 +1100) it happened Grant >>>><omg@grrr.id.au> wrote in <n407j7lfbg9bes8dvd5gcse7e46c68lpk4@4ax.com>: >>>> >>>>>Maybe? Technique I used basically shorted the battery for a very >>>>>short time, >>>> >>>>Seems like amateur crap to me. >>>>Shorting a battery. >>> >>>Company got a patent on the technique, so it must've been bad ;) >>> >>>Grant. >> >> There have been patents issued on perpetual motion machines. >> >> You would not want to 'short' the sort of batteries I have been around, >> size of a room, the switch and wiring would evaporate immediately. >> 1 uS would be far too long, > >assuming 6.3kg of copper wiring >it's about 30Mj to vaporise it, giving your batteries a peak power >ofOVER 30TW, impressive. > >How did they get the inductance so low on a battery that size?
You are confusing 2 things: inductance only is important for very short pulses. A say silicon switch will be destroyed within 1 uS due to hot spots at a much lower current then you refer to, and then will become a very good conductor. (usually those go short). Then the rest of the time, much longer than that 1 us, the copper melting process takes place. Here a low current demo: http://panteltje.com/pub/power_pic/when_things_go_wrong_img_0885.jpg the switch was over loaded, and faulted to the 'on' state. After that the wiring caught flames. This was about 10 A from a small 12 Ah battery. Now imagine a bigger setup. In this case the high resistance of the wiring limited the current. I once did a 2 thyristor tuned 50 Hz (balanced) sinewave converter, in such a setup the reverse voltage swing turns of the other thyristor, and then one thyristor did not switch off... This was powered from the biggest nicad you have ever seen, IIRC 64 V room size, Thyristors are beasts. :-) And yes, rat-head sucks, and yes, video4linux is a disaster. Linux is heading the mirobug way.