Joule Thief

[crowclaw]

@ MK1, what do you mean ?

@ All, I have just put my Solar panel and frame up outside, running with a 14 meter (15Amp) cable.

However when connected to DMM or analogue meter, it reads about 5 Amps through the 14 meter cable,
but if I dont use the long 14 meter cable... I get  9-10 Amps, why am I loosing  4-5 Amps through the cable ??
Oh, the volts are at about 2.5-2.6 with short or long cable.

Your cable has a specific resistance per metre as already mentioned. The longer the cable length the greater the resistance , similar to adding resistors in series. Resistance restricts the flow of electrical current. Is your cable solid core or multi stranded?... a conductor has what's known as the 'skin effect' where the current passes along the outer or skin of the conductor. You could try a multi stranded cable of sufficient amperage and diameter to reduce the losses. Multi stranded cable has many conductors and effectively they are all in parallel, combining resistors in parallel reduces resistance ( Basic Ohm's) also make sure all you connections are good. Hope this helps. Regards

[Mk1]

Money is going down this week apparently . New treasury Money , and Dinar for Oil .

[dasimpson]

i was woundering could a zener diode and a relay be used as a simple charge controller

[resonanceman]

i was woundering could a zener diode and a relay be used as a simple charge controller

\

Dasimpson

It should be possible to use a zener diode as a switch to control the voltage.
Personally I do not like relays ,they are noisy and not very reliable.

Here is a circuit I started a while back......it is not perfected yet......but I have did some basic tests.
I use a LED where you may want to use a zener diode.
I chose a LED because I wanted a charge indicator light.
A LED switches on pretty slowly as the LED gets brighter.
Like a zener a LED will pass very little voltage below a certian voltage.


The schematic  is a little confusing.
It is intended on showing just the voltage control part of the circuit.......but the battery at the top should  also be used to drive the JT that is charging the U Cap.

The U cap is shown  with dots ( terminals ) on its ends.........the rectified output of the charger  would be connected at these points.

The coil shown in the drawing is not  for charging the U cap.......it is an extra winding added to the JT.
I am sure  you have tried many windings  that prevented the JT from working......that is how this  coil works........ before the transistor  turns on the coil has very high impedance and does not really effect the circuit much......as the transistor  starts conducting this coils impedance drops, in effect  sucking the power away from the normal secondary........this power is then fed back to source.

From my experience the white LEDs I have start conducting at just  under 2V.........the variable resistor there to allow adjustment of the final cut off voltage......

I like this circuit  because it is simple .......it gives me an indicator light  and it is completely passive until  the U cap is mostly charged


I hope that this helps


gary

[NickZ]

  Gary:
  I'm wondering if by placing any Led between the C and E of any of theses JT type circuits as an indicator light etz...can limit the amount of juice that can flow through the whole system? Thus limiting the circuit to the usable voltage and current of that led diode, to some degree, even if there is a secondary.  Isn't it better to have less restrictions, like no resistors, diodes, pots, leds, etz.. but control the voltage by lowering it, so they are not needed? As they may all be consuming part of the tiny output current and dropping the efficiency of the circuits as well as the brightness of the light.
                                       NZ