another electric fence problen

Tomjim

Hi

I have a mains fencer and it is perfect after 20 yards, however when it goes to 50 yards it becomes very weak. I have tried everything, it does not appear to be earthing anywhere.

However tonight I noticed that the guy who installed the fencer, earthed it into the main ESB fuse box. He included the fence EARTH wire with the Earth wire (ESB earthing), the ESB wire I assume is copper and is touching off the fencer earth wire, is this what is causing my problem?

bbam

The guy who installed the fencer is a MORON

ASAP you need to run the earth of the fencer outside to a proper fencer earthing system. 3 steel stakes, 1 meter in the ground and a minimum of 1 meter appart. The damper the location the better.

I wouldnt have the fencer running connected the way it is as it may possibly be feeding back into your esb mains. Which would certainly damage any sensitive appliances connected.

Copper wire shouldn't be used in any stretch of a fencer, steel wire all the way.

Tomjim

could I earth it to one of the girders in the shed

bbam

You could but that won't work well either. Probably be safer than the current setup.

If you want the maximum benifet from the fencer you'll need a setup as I described above. Anything else will limit the potential output of the fencer.

The girder is set in concrete in ground covered by a shed. It will be snuff dry and carry no real current. As the fencer is used the voltage will desperately try to get to ground and likely cause stray voltages throughout the shed framework. You may not notice this but any stock will , particularly if they are in a parlour.

49801

earthing def the problem here all right.
lighting rods are taller than standard earth rods too... I think they'd be worth the extra myself.

I was advised to cover the wire to rod connection with 'densing' tape. its really nasty sticky stuff horrible to work with. But it will keep your connections clean so you keep a good wire to rod connection

to make the connections I stripped the outter insulation and wrapped it around the rod as tightly as I could. bolted on the U-clamp over the wire and then covered with the densing tape. I did not cut the earth wire once. So it is a solid wire going from the fencer to rod1 to rod2 to rod 3 to rod 4.

Use good quality steel wire (2.5m^2?).... I'll be spending the next few years removing all the copper wire that was used:mad:;).

snowman707

bbam wrote: »

The guy who installed the fencer is a MORON

ASAP you need to run the earth of the fencer outside to a proper fencer earthing system. 3 steel stakes, 1 meter in the ground and a minimum of 1 meter appart. The damper the location the better.

I wouldnt have the fencer running connected the way it is as it may possibly be feeding back into your esb mains. Which would certainly damage any sensitive appliances connected.

Copper wire shouldn't be used in any stretch of a fencer, steel wire all the way.

+1

I read op's post earlier but refrained from replying as my choice of words most likely would got me banned

I can't remember off hand but esb's recommendations for earthing an electric fence is that the fencer earth is a minimum of 20 mtrs from the main earth,

OP

good advise already given

the present system or as you mentioned (pillar) as well as giving you poor performance is also going to put stray electricity floating

an old copper cylinder buried in the ground is a good earth

http://www.cheetah.ie/index.php/help-safety/installation-earthing/

bbam

Enough with the copper.

How do you intend to connect the copper to the steel wire without the problems of the reaction of dissimilar metals causing insulation layers thus rendering it useless.
You could bury a piece of rsj or similar steel object but not copper, you'll just be redoing it in the future.

However I'd recommend sticking with an earth rod system. It keeps the connections accessible for future testing without a digger.

Best practice demands all steel components to the system.

snowman707

bbam wrote: »

Enough with the copper.

How do you intend to connect the copper to the steel wire without the problems of the reaction of dissimilar metals causing insulation layers thus rendering it useless.
.

reactions cannot occur without the presence of air and moisture


we use an copper rod earthing system in an activity I am involved in, ok I admit the extremes we go may not be practical for farming


the system in situ since early 1990's and still performing as day 1.

bbam

Oxygen and moisture cause the reaction. Both of which are present in soil.
Ok if it works for you I'll yield to the notion.

But if you notice none of the fencer suppliers recommend copper wire or copper cylinders.

pakalasa

In fairness you can see why an electrician would connect both earths together. In normal electrical work all earths are connected, domestic, industrial machines etc. The earth is in effect redundant and just for safety.
With a fencer, the earth is the return line. So in effect the earth does the job of the neutral.
As for copper, copper is a far better conductor of electricity than galvanised steel. Granted it does corrode like mad though.

gazahayes

Denso tape to seal up any joints on the earth bars great stuff but awful to try get off your hands. Handy for sealing holes in pipes too.

LostCovey

I just bury a length of galvanised wire in a long trench as an electric fence earth, seems to work fine

bbam

pakalasa wrote: »

In fairness you can see why an electrician would connect both earths together. In normal electrical work all earths are connected, domestic, industrial machines etc. The earth is in effect redundant and just for safety.
With a fencer, the earth is the return line. So in effect the earth does the job of the neutral.
As for copper, copper is a far better conductor of electricity than galvanised steel. Granted it does corrode like mad though.

Not really.
The whole distribution system is 240v ac while the fencer output is about 10,000 volts dc. High voltage dc and low voltage ac should never be mixed.
The guy hadn't a clue.

Yes copper is a better conductor but the issues with electrolysis at joints with dissilar metals is a serious problem. And will render the system useless. Best practice dictates using all steel wire. Why not do it right and have a system that lasts for years rather than one that starts to degrade within a year. I've seen copper having to be replaced within two years as the fence wouldn't work. In an extensive network this is a pain.

snowman707

snowman707 wrote: »

reactions cannot occur without the presence of air and moisture


we use an copper rod earthing system in an activity I am involved in, ok I admit the extremes we go may not be practical for farming


the system in situ since early 1990's and still performing as day 1.

bbam wrote: »

Oxygen and moisture cause the reaction. Both of which are present in soil.
the joints are treated with jointing compound before assembly and then thoroughly sealed to prevent oxidation
Ok if it works for you I'll yield to the notion.

But if you notice none of the fencer suppliers recommend copper wire or copper cylinders.

for the reason you mentioned , ie 99% of farmers won't go to the trouble to do it properly

.

pakalasa

snowman707 wrote: »

...we use an copper rod earthing system in an activity I am involved in, ok I admit the extremes we go may not be practical for farming....

Is that for Lightning protection?

Bruthal

pakalasa wrote: »

In fairness you can see why an electrician would connect both earths together.

I can see why some of them would alright, but not good ones. This is something any decent one should know to avoid.

bbam wrote: »

Not really.
The whole distribution system is 240v ac while the fencer output is about 10,000 volts dc. High voltage dc and low voltage ac should never be mixed.
The guy hadn't a clue.

Its not because of the 2 different systems that its not working well though.

It would actually work well if the electrical installation was connected to ground well enough. But on a farm with a likely single transformer dedicated to the installation, and likely only 1 single earth rod (if even that) connecting the installation to earth, it just would`t be good enough for a fencer which depends on a good earth connection as part of its active circuit, to work. Individual electrical installations dont need a good quality earth connection to the actual ground, contrary to what many might believe.

If the same setup as in the OP was done in a housing estate, the fence would work well, due to the many earth rods connected together through all the houses being neutralised, as well as all the neutral bars at mini pillars being earthed, so there would be a very large earth grid.

But anyway, I completely agree, electric fence installation earths should never be connected to electrical installation earths as said.

pakalasa

I put down an electric fence today with high tensile wire. The fence runs along the side of a deep trence of water. It's a portable fencer with a short earth bar as part of the fencer stand. I was thinking of putting a bit of wire into the water itself as an earth. It should give the 'mother of all earths'. Anybody ever do this?