Electric Fence Zapper

[bj]

   That is seriously tidy.  The info, and review of service will be a boon
to many in the future I am sure.
   Thanks for the share Dario.

[Dario]

Hi to all and sorry for delay
Since a lot of members asked me for gerber files i will add them into post.
The pcb is 98% like oztules pcb only i did my in eagleCad + minior change
Notice that capacitor's used for trippler and "snubber cappacitor" i used is pitch 22.5mm because they were available here in Croatia
All "thanks" goes to ----oztules----

I am still waiting for some components to finish pcb but the main high voltage transformer is done and i will send some photo later.
For insulation of transformer Kapton tape + bakeing paper ( double or tripple layers between primar and secundar) were used, it should be fine since Kapton and this paper is high temp ressistance + kapton is one of product  used in transformer production of new generation.

...Dario

[Dario]

Here are some photos of production.

[oztules]

looks beautiful...... makes mine look primitive

Hope you have a decent core for the transformer.


..............oztules

[Dario]

Hi oztules again, i ve finished the trippler board and it is working but the 680 ohm resistor is overheating very fast, did you ever had this situation?? I am using 3W.

Thanks
Dario

[oztules]

The 680 used to get very hot, but less then 90c as a rule.... but it should not discolour.
You can use a 5w or more resistor there... I find that I have been doing that for the last few... ran out of the 3w units.

Whatever you put there will get hot, as it dissipates a fair bit of power.

I just lift the resistor above the board so it does not cause any board heat.

If you want, decrease the size of the caps ( the 1uf ones) on the input side, and you will reduce the current draw, and can use a lower value of resistor to compensate.

I use what I have handy... and I had a few hundred 1uf caps at the time.


.......................oztules

[Dario]

Oz thanks for info, but i think in my case problem is in output transformer. I Read some posts and i did primary 9 turns 2 in hand ( bifilar paralel), and later i found you wrote 22turns 2 in hand ? :-)
I will Do some more winding :-)

[Dario]

Small update :-)
The HV voltage is without load, in some point it reach 10.4KV
Since i am using dc to ac converter i removed the resistor 680ohm from the main input.
This unit does drain a lot of ampers in peak.

[mukptl]

please see pic for new layer starting  which ok A or B
thanks

[frank]

B

[mukptl]

this machine can run without load on output ? (open circuit )
mean without connection to fence wire
thanks

[oztules]

Yes, but will put a lot of pressure on your insulation in your transformer... try to avoid this situation if possible... or put a resistor across the output ( 500R) to keep the peak volts down, and stop the chance of interwinding shorts in the tranny.... it shouldn't... but don't tempt it either.

I use plan B in your question above, as the potential between wires is the least where the layer wires transit to the next layer


Dario, for battery electric fences, power drain is a significant problem with the design, I had not thought at all about power drain with the ac model, as keeping animals in is more important than power cost.. any cost.....

But a battery needs consideration, so you must be more attune to economy.. if you want to do dc, then suggest you go with the dc version, very very much less power required from the battery

.............oztules

[mukptl]

Thanks oztules
i have same invert transformer 20 & 500 turn but  with one  primary winding no feedback primary winding
that will work ? can use feedback from secondary winding ?

[oztules]

Not sure if it will start in that configuration.... If you can get it to start it should work.
It is a VFO, so not sure how it will work over the range..... try it and see.

..oztules

[RFburns]

 So I have built a couple of these and given them to various people and here is a tip for very long fence runs or if the ground is very dry. RF

For VERY long fences, or VERY dry ground: RG6 Coax makes a nice high voltage capacitor. Make a coil of the coax at some point mid-way of the fence, and connect the centre to the fence, and the shield to ground. You will get between 17 and 18 Pf per foot. Doesn't sound like much, but it will bite ! .A couple of these placed strategically will keep the power up.

A bit crude but cheap and easy.