temporary electric fence

[not_today]

please note this "project" is for my own personal use and will be carried out in my (well mum and dads) property. I would just like some advice on how to do it safely and economically. I would post this in the other part of the forum but i fear for my sanity ......

In the next couple of weeks myself and my family are planning to make a concrete base for our pigs in their enclosure. unfortunately, they cannot be moved out of it whilst we are working and we therefore need to keep them away from our work area for 24 hours whilst the cement hardens etc.

to achieve this i plan to set up a temporary electric fence around the area using the proper wire, insulators and wooden posts. i have plenty of both of these but the only problem is that i have no energizer to power it.

i do however have a couple of car batteries which i was thinking of hooking up to the wire to provide power. they still hold a charge but the person who stored them here has moved away and i would rather knacker the battery i have for free instead of buying a new energiser which will only be used for a few hours.

it doesn’t need to keep giving a shock for 24 hours, I reckon the pigs will touch it a couple of times and keep well away until the cement has hardens. it just needs to last a couple of hours or so.



what do you guys think?

Can i work out how long it should last if i now the distance of the wire needed (10m), the resistance (o.12ohm/m) and the cable size (0.5mm2)?

Sam

 

[davesparks]

An electric fence pulses at around 10,000 volts for a fraction of a second every few seconds.
Two car batteries in parallel could give you a permanent 24volts.
Not quite the same thing!

 

[not_today]

and this is why i didnt post it in the other part of the forum ...... dont i feel silly!

any ideas?

 

[Richard Burns]

There are these high voltage step up power modules available for sale for a couple of quid on ebay that run on a 3V battery and effectively produce a small spark of several kV when connected, I do not think they would actually have enough power but I have never tried them.
However if you were to connect them to a 12V battery (check that they can take this voltage) and had a pressure switch or micro switch set up so that when the fence was pushed it connected to the fence and ground this might work, though knowing pigs they would just continue to press and ignore the first shock and so go straight through unless you could set up a pulse system.
Obviously this is for a short length of dry fence.

Probably a very silly idea. but just a thought.

 

[Marvo]

You can make a home made one from an old style, cylindrical shaped car ignition coil. It must be one of the older type because the newer car ignition coils often have other fancy bits and pieces built into them.

You need an arrangement that will supply the ignition coil with switched 12VDC so there would be a small circuit you'd have to build with a 555 timer and a transistor. You'll also need an earth rod with a half-decent Ra.

I'm a bit wary of this kinda project for a beginner because one false move and you'll get defibrilated in a big way....or someone else will, the output could be as high as 30 or 40kV which is 3 or 4 times higher than the normal energisers. TBH you're probably better buying a really basic fence energiser off e-bay like this one.

 

[telectrix]

i'm with marvo here.

 

[Paul.M]

i'm with marvo here.

Same here. It only costs £30 + p&p and can be used again if need be, or just sell it and get your money back? Good question though, but I would just buy one.

 

[not_today]

thanks for the advise again chaps ....

I spent today digging out the base or the hard core to go into and I have managed to place the topsoil in such a way that the pigs cannot get to it. I know its only a temporary measure but its not needed for long!

 

[Marvo]

I've owned a pig when I was living in the US and believe me, if they want to get to it they will. I built a wooden pen for mine with poles that were over a meter in the ground and the damn thing still managed to dig its way out. For an encore it ate a load of washing that was hanging out to dry and it pulled the fridge door of its hinges and devoured the entire contents including ice trays.

 

[Richard Burns]

thanks for the advise again chaps ....

I spent today digging out the base or the hard core to go into and I have managed to place the topsoil in such a way that the pigs cannot get to it. I know its only a temporary measure but its not needed for long!

Well, that is thinking outside the pig pen isn't it?