# Electric fence energiser..will a 6 v do??



## apple88 (2 June 2011)

Hi,

electric fence dilemma....
Firstly. Ive seen zappers that run off 4 D size batteries, think thats 6v...is that enough for a small-ish paddock?

Also my friend has a zapper, it takes 4xD size batteries, and has attachments for a car battery. But she said that the car battery charges the small batteries? ive just read on a website for fences that you should remove the small batteries before connecting to car battery...so am a bit confused..

many thanks


----------



## Rob Lakeside (5 June 2011)

Hi Jennygrace

The volts are not the issue, it is the Amps that are the importantance.

4-6-12 volts produce the same amps, it is the amps that cause the kick, the zapper converts the volts to Amps and it is the amps that make you jump.

So the zapper converts up, not down and the amps increase to a level that zaps the horse, this is set inside the zapper( *and is why you never take one apart)*  and if and when the batteries have not enough energy(volts) the amps are not produced. 

But this is why you can take a shock from a kettle lead etc. and not die but the shock from the fence seems worst working off a car battery. 

Your mobile phone trasformer works off a 13amp fuse and 240 volts ,so low amps high volts,  and the phone transformer converts down to 1-5 volt and vary low micro-amps 

Amps and volts, it is the amps that kill not the volts
or you can take 10,000 volts but 30 amps will kill you, (as found in the back of ovens and electric hops) 

Hope this helps


----------



## Rob Lakeside (5 June 2011)

To add
4 volt batteries do not last as long as 6 volt batteries and same for 12 volt last longer still and 24 volt batteries would last months but you cannot get them and if you could, you would not be able to lift due to the size.


----------



## TheEngineer (7 June 2011)

Hi, not posted for a while but thought I would answer you query. As whilst some of the answers given are half right, things are slightly more complex.

A six volt energiser will be fine for a small paddock, dividing a paddock or running short fences. The six volts supplied by the 4 d cells is put into a transformer that steps it up to approx 200 volts, that is then fed into another transformer that takes 200 and jumps it up to approx 8000 volts. This voltage is fed onto the fence at one second intervals to shock the horse. The important factor in any fencer, is JOULES (not the clothing company) But a measurement of the stored energy that is fired into the line. The more joules, the better punch the fencer will deliver, which is why for equestrian fencing lower joule fencers are adequate, but for sheep and pigs, deer etc you need more shock to stop the animal so higher joules are needed.

The downside, is that the higher the joules, the more power is taken from the battery to create the shock and the quicker it will go flat. So it is always a trade off between power in/power out and battery life.

I will usually recomend a 12 volt fencer, if you are able to recharge the battery regularly. If you are happy to throw away d cell batteries, then a six volt unit will be fine. Long term a mains fencer will always be cheaper, if you have access to mains power, if not why not consider a solar unit. I know Wolseley have a superb new unit out called the SX300 which is powered by the sun and has internal backup batteries, other manufacturers also do solar units. If you want any further advice feel free to PM me

Regards


ian (the engineer)


----------

