Mains fencer earthing

madfeen

Active Member
I have a question about mains fencers; does vegetation touching the wire (grass, ferns, nettles etc.) degrade the shock much? I had to go around the fields there on Saturday because there was no light on the mains fencer tester when I tested it. After several hours cutting away grass, nettles, briars, ferns etc. there was one light then (at the bottom of the land by the river which is where I need the shock as strong as possible).
Better than nothing I suppose but I thought it would be better. I cut away as much as I could but there were a few places where there were rushes touching it and I couldn't cut them, there were too many. The fencer is only a couple of years old, it is an Elephant M40 (230 volts). I was unable to find out how big an area it should cover, I think I read somewhere it should do 20 kms. The area I farm is about 50 acres but I have two fencers. The M40 covers about two thirds of that and the other fencer covers the remainder. There is a much better shock off the fencer that covers one third. I don't know what voltage is on that because the label is worn off it.
I was thinking of getting another fencer but I'd prefer not to. I work during the week so I wouldn't be able to go around checking the wire. I'd be a bit paranoid about cattle breaking out (the land is rented). I can't give it my full attention.
 
Anything touching the wire that will let it leak back to earth will reduce the voltage, vegetation that is wet is even worse, the earth connection from the fencer unit to ground is also a possible cause, ideally a few earth bars connected together and in a damp spot if possible is better than into a gravel base.
 
One light isnt good enough anyway.
Make sure the fence itself is earthed sufficiently, disconnect the fence line at various intervals and check shock to isolate where the worst problem might be.
 
first of all check the earth of the fencer itself, you should have at least 5 earth bars spaced in a semi circle if possible about 5 or 6 mtrs apart bonded with under ground cable and joints sealed with denso tape

next check any place the fence line is joined , and re do the joints if necessary . if you could knock off sections of the line and check the voltage .

we literally spent days looking for a fault in the out block , finished up finding a that the hedge cutter must knocked the previous autumn and the tail end was in a drain


(EDIT I'm slow on the keyboard others have posted while I was typing but I'll leave the post as it is )
 
As said above anything touching the wire will pull current out of it. Sounds like a wire is touching the ground or something metal? Might be worth wetting up the area around the earth bars too.
 
It definitely isn't touching the ground anywhere or touching any metal. My question has been answered though; yes vegetation will degrade the shock from the fence wire, I was told by someone it wouldn't, that only metal or if the wire is hanging on the ground will.
I don't have the time to do the other stuff suggested (five earth bars etc.). Disconnecting it at intervals and turning the mains off and on again is too time-consuming also; I would have to go back and forth between where the fencer is plugged in (I am on my own).
Unfortunately I am not one of those people who can catch hold of the live wire and tolerate the shock.
Sure cutting away grass, nettles etc. is a losing battle anyway; I could go around the entire farm tomorrow and cut all that stuff and next week it would be the very same again. Another fencer might be the best option.
 
These questions about mains fencers with no power output regularly come up here. In my experience its rarely a problem with the fencer unit . The best sap on power is if the electrified wire comes in contact with thorny wire or worse if it makes contact with sheep wire. Vegetation in contact is usually a lesser draw on power. If the Vegetation is wet this will double the draw.

I never turn off the fencer, you can disconnect a section with an insulated pliers, often done it with a wolly hat , Biro, bit of timber etc etc
 
I have a question about mains fencers; does vegetation touching the wire (grass, ferns, nettles etc.) degrade the shock. The fencer is only a couple of years old, it is an Elephant M40 (230 volts). I was unable to find out how big an area it should cover, I think I read somewhere it should do 20 kms. The area I farm is about 50 acres but I have two fencers. The M40 covers about two thirds of that and the other fencer covers the remainder. There is a much better shock off the fencer that covers one third. I don't know what voltage is on that because the label is worn off it.
I was thinking of getting another fencer but I'd prefer not to. I work during the week so I wouldn't be able to go around checking the wire. I'd be a bit paranoid about cattle breaking out (the land is rented). I can't give it my full attention.
230 volts is the mains supply, the fencer gives out a pulse of 5000volts, if you swap the fencer units and the result is the same the problem lies in you fence wiring leaking to earth somewhere.
 
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Is your lead out cable in good order? Galvanised insulated deally. Not Copper. Vegetation in dry weather would matter less than the earth in the same weather .it will however absolutely kill it in wet weather.

Steelwork also for fencing is the ideal choice as opposed to polywire for current to travel & keep consistent
 
Firstly disconnect live wire coming from fencer unit and put fence tester to the unit bolt, if giving full lights there you know unit is working fine so either not earthed well enough or herbage problem
 
We have the cheetah equivalent of that fencer and it's well able to keep vegetation burned back. The only time it's under pressure is when ferns bend over and double over the wire.
 
It definitely isn't touching the ground anywhere or touching any metal. My question has been answered though; yes vegetation will degrade the shock from the fence wire, I was told by someone it wouldn't, that only metal or if the wire is hanging on the ground will.
I don't have the time to do the other stuff suggested (five earth bars etc.). Disconnecting it at intervals and turning the mains off and on again is too time-consuming also; I would have to go back and forth between where the fencer is plugged in (I am on my own).
Unfortunately I am not one of those people who can catch hold of the live wire and tolerate the shock.
Sure cutting away grass, nettles etc. is a losing battle anyway; I could go around the entire farm tomorrow and cut all that stuff and next week it would be the very same again. Another fencer might be the best option.
Spray the weeds or pay someone to do it
 
But seriously though, does every single farmer go around their land spraying weeds, cutting every single blade of grass, thistles or anything that is touching the fence wire? I know from looking over the ditch to my neighbour's land that his fence wire has grass and everything growing around it all the time (and he's farming full-time, I am not). Even when I am out driving I see it inside ditches, nobody went near that wire in months, even years I would say. I'm not saying it's right, just saying what I see.
 
Don't spray here but if I need a wire on, I just make sure to go around and clear it. A simple thing to make sure animals stay in. Part time farming here, so really don't have time to be chasing and catching animals off farm.
 
Ah I wouldn't bother me hat about it. Sure the cattle will eventually bate down all around it. An odd pallet into the weak spots eventually if ya have to
 
We don’t have many hedges/ditches fenced, we’re lucky to have good thick hedges with our neighbour, his side isn’t fenced either. Two fields are fenced all around because they’re a bit weak, probably go around them 2/3 times per year cutting back the vegetation and rushes with the petrol trimmers, don’t like using spray - only for spots the hedge cutter won’t get to. Can generally see substantial difference once it’s cleared off
*mostly dairy here, cows are easier managed. Will be doing more permanent fencing as there’ll be more dry stock going forward
 
But seriously though, does every single farmer go around their land spraying weeds, cutting every single blade of grass, thistles or anything that is touching the fence wire? I know from looking over the ditch to my neighbour's land that his fence wire has grass and everything growing around it all the time (and he's farming full-time, I am not). Even when I am out driving I see it inside ditches, nobody went near that wire in months, even years I would say. I'm not saying it's right, just saying what I see.
Yes and twice at that
 
But seriously though, does every single farmer go around their land spraying weeds, cutting every single blade of grass, thistles or anything that is touching the fence wire? I know from looking over the ditch to my neighbour's land that his fence wire has grass and everything growing around it all the time (and he's farming full-time, I am not). Even when I am out driving I see it inside ditches, nobody went near that wire in months, even years I would say. I'm not saying it's right, just saying what I see.
All done in late April/ early May, will walk it all again soon to kill any straggler nettles and thistles.
 
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