Electric fence chargers

[Alan]

2 questions for you;

1. I have enough electric wire out that I want to add a second charger and can do it since I have two different fence, unconnected fence systems. My first question is can I piggy back just the ground wire from one box to the other box, which is hooked to the ground rods without a problem. So in other words instead of running a long ground wire to the rods from the second box, just run a couple of feet from the ground terminal on one box to the ground terminal to the other box and then down to the rods?

2. They seem to be changing the laymans terms for power rating on the hot boxes since I purchased my last one. I have a 15 mile fencer now. The ones I'm finding now are in acres. Is there a power reading I can find that will give me the output or strength of a certain box?

Thanks,
Alan

 

[dun]

There isn't any easy way to comare fencers from different manufactuers, they all use a method pf quantifying their chargers to make them look good.
You'll need 2 ground systems and seperated by a very minimum of 25 feet from each other, 50 feet is better.

dun

 

[tom4018]

Most chargers are rated by joules, the more joules the more power and capacity.

 

[Texas PaPaw]

Alan

1. You need a separate ground system for each charger.

2. While not a perfect measure, joules are about the only common denominator for comparing chargers. Most manufactures rating are extremely optimistic and are based upon ideal conditions with no vegetation load (grass, weeds, brush) to bleed off voltage. You should be able to get a joule rating for each charger to compare. Beware some mfg state output joules, while other give stored joules. OUTPUT joules are what count. If only stored joules are quoted, reduce them by 25-50% to get the equivalent output joules. According to the Missouri Grazing manual & grazing consultant Jim Gerrish, they recommend 1 output joule per mile of fence. Don't skimp on your charger size & the number of ground rods, unless you want to be running a weedeater under your fence all summer. I currently have over 3 miles of fence on a 6 joule charger and it always maintains 5000+ volts (regardless of grass & brush load) unless there is a direct short between the fence & a steel post. Even under the worst conditions, my fence stays hot enough the cattle won't mess with it. Just my 2 cents worth.

Good luck & happy trails.

Brock

 

[S.R.R.]

Alan

1. You need a separate ground system for each charger.

2. While not a perfect measure, joules are about the only common denominator for comparing chargers. Most manufactures rating are extremely optimistic and are based upon ideal conditions with no vegetation load (grass, weeds, brush) to bleed off voltage. You should be able to get a joule rating for each charger to compare. Beware some mfg state output joules, while other give stored joules. OUTPUT joules are what count. If only stored joules are quoted, reduce them by 25-50% to get the equivalent output joules. According to the Missouri Grazing manual & grazing consultant Jim Gerrish, they recommend 1 output joule per mile of fence. Don't skimp on your charger size & the number of ground rods, unless you want to be running a weedeater under your fence all summer. I currently have over 3 miles of fence on a 6 joule charger and it always maintains 5000+ volts (regardless of grass & brush load) unless there is a direct short between the fence & a steel post. Even under the worst conditions, my fence stays hot enough the cattle won't mess with it. Just my 2 cents worth.

Good luck & happy trails.

Brock

Are you sure it is 1 output joule per mile of fence? The highest I can find is still only 15 joule output! It says it will cover 200 miles of fence and is the strongest made in the US.
Here is the link.
http://www.zarebasystems.com/products/f ... owimp.aspx

 

[Texas PaPaw]

Alan

1. You need a separate ground system for each charger.

2. While not a perfect measure, joules are about the only common denominator for comparing chargers. Most manufactures rating are extremely optimistic and are based upon ideal conditions with no vegetation load (grass, weeds, brush) to bleed off voltage. You should be able to get a joule rating for each charger to compare. Beware some mfg state output joules, while other give stored joules. OUTPUT joules are what count. If only stored joules are quoted, reduce them by 25-50% to get the equivalent output joules. According to the Missouri Grazing manual & grazing consultant Jim Gerrish, they recommend 1 output joule per mile of fence. Don't skimp on your charger size & the number of ground rods, unless you want to be running a weedeater under your fence all summer. I currently have over 3 miles of fence on a 6 joule charger and it always maintains 5000+ volts (regardless of grass & brush load) unless there is a direct short between the fence & a steel post. Even under the worst conditions, my fence stays hot enough the cattle won't mess with it. Just my 2 cents worth.

Good luck & happy trails.

Brock

Are you sure it is 1 output joule per mile of fence? The highest I can find is still only 15 joule output! It says it will cover 200 miles of fence and is the strongest made in the US.
Here is the link.
http://www.zarebasystems.com/products/f ... owimp.aspx

S.R.R.

Quoting from the Missouri Grazing Manual page 90 "At the University of Missouri Forage Systems Research Center (FSRC), experience has shown that allowing one mile of fence per joule output will give satisfactory performance in most situations." I think the key words are "in most situations" as opposed to ideal situations. Less output could do the job in ideal conditions of low humidity & no vegetation touching the fence.

IMO 200 miles of fence on a 15 joule charger would be overly optimistic even in an arid range grazing situation. I tend to give more credibility to the recommendation of a neutral 3rd party user (FRSC) than the folks selling the product.

FWIW my 6 joule charger is rated for 100 miles. Wouldn't think of putting even 10 miles of fence on it my area. Leased some grass from a neighbor with 1 mile of electric fence. He had a 5 mile rated fencer. After a couple of weeks a set of gentle cows that were trained on a 5000+ volt fence were crawling thru the fence with the wimpy 5 mile charger. Put the 100 mile, 6 joule charger on and stopped the fence crawling immediately. The higher the humidity and/or vegetation load + more wire, the more voltage bleed off you get. It takes a powerful charger to overcome this voltage loss.

It has been my experience that an extremely powerfull charger + an adequate grounding system will eliminate a lot of headaches & heartburn even in very difficult situations.

'Nuff said

Good luck & happy trails.

Brock

 

[dcara]

[/quote]You'll need 2 ground systems and seperated by a very minimum of 25 feet from each other, 50 feet is better.

Dun - I don't understand the need for 2 different grounding systems, or the separation. Could you please detail the technical justification or reference for this.

 

[dun]

You'll need 2 ground systems and seperated by a very minimum of 25 feet from each other, 50 feet is better.

Dun - I don't understand the need for 2 different grounding systems, or the separation. Could you please detail the technical justification or reference for this.

[/quote]

A given ground system can only be just so effective. When there is poor soil conductivity the first part of a powered fence system that fails/deteriates is the ground. I don;t know all the scientific reasons but we tried 2 chargers through 12 ground rods each rod about 10 feet from the other. First of all it got toe be a mess with that much stuff strung under the fence line, secondly it never seemed very effective. We moved one charger and put down 4 rods and both chargers performed better. I know there has to be some electrical gobelygook about why but I don;t know what it is. Maybe one of the electrical type folks can better address the why's.

dun

 

[AngusLimoX]

Once in a while I get lucky making decisions around here, and not skimping on my energizer or ground system were 2 of them.

The energizer is rated at 18 joules by the company, and puts out 10,000 volts. I have heard 9 joules is a good minimum for beef.

I did have to pay almost $800 canuckle bucks for it but in my opinion it has paid for itself. I hate chasing cattle!! That and there are a lot of cash crop boys around me who would not be very happy with my mutts trompin through their crops.

I have a bunch of paddocks all with a single offset hot wire, on 200 acres. Rarely see the voltage below 8,000.

It is truely entertaining to watch the new calves "learn" about the fence. "Snap/Bawl" is heard often in these parts in spring.

What convinced me was when I first let them out on pasture in spring a couple years ago, and about 30 of them made for a big open part at full speed. The skidmarks they left when they spotted that single HT wire were impressive! :lol:

 

[lukem86]

maybe this is really simple and i just dont get it but..

When you guys talk about "miles of fence"....

If I have 5280 perimeter feet of fence and I have 3 hot wires and 2 ground wires, do i have 1 "mile" ,3 "miles" or 5 "miles" of fence as talked about above?

 

[Angus Guy]

3 miles. Each strand is a seperate fence.

 

[jgn]

miles of fence = total distance of all hot wires.

 

[Herefordcross]

A ground is a ground, you can ground 10 chargers to one ground 1.)If the wire to the ground and the ground rod will take it 2.)If you understand that if lightning hits the ground it will fry both of your chargers possibly??

 

[dcara]

Thanks Dun. I agree that grounding systems often fail, and can cause some pretty unusal symptoms when they are not working properly. I designed some portable power systems for the Egyptian military back in the 80's (paid for by the US gov/taxpayer). When we went over and did the acceptance tests at one of their forward bases in the Sinai we had a terrible time getting the grounding system to work properly in that sand based cement they call soil. Not sure what was happening with your system but technically I think a common ground system for 2 different fence chargers should work. FWIW.

 

[Bama]

Earth is earth, Dirt is dirt, and Ground is ground. A single ground source will provide for many systems. I don't mean one rod driven in the ground I'm referring to a good solid contact with ground. In most cases folks try running a small wire to the grounding setup. The resistance of this wire coupled with the poor conductivity of the dirt causes a failure. A good solid contacting ground system may require a delta setup. (3 rods in a triangle) In some cases more rods or deeper rods are required to achieve a solid contact. The moisture in the soil is a key factor in this. A good place to put ground rods are at the drop line of the roof on the barn. This normally stays wetter and provides a better ground. If you don't have a good solid ground it is better to seperate them to prevent any bleedoff. If you seperate them you can get by with a lesser grounding system.
As far as miles of fence, you can't really pay much attention to that. One big factor is the way you put them on the post. If they are run in one continuous line then you have the resistance of all of that wire. By this I mean running a wire down to the end and then comming back to the start and back down again. To reduce the resistance load run a wire down and back and tie them together every so often. By tieing them together you cut the resistance down dramatically. Say you run 5 strands down a fence, tie them together ever few hundred feet or so. If you don't tie them together you have in effect one really long wire. If you chose to run one wire grounded down the fence make sure your tiein can't contact it.