How deep is the wire?
If we ran our installation machine (as opposed to hand installation) the wire will most likely be three to six inches in depth. However, it is shallower where we encountered tree roots or rocks. In areas where we knew or suspected there are phone lines, cable TV lines, outdoor lighting lines, drains, sprinkler control lines or sprinkler heads, your line is also much shallower so we could avoid damage to these facilities.
Over time, tree roots and erosion will expose or lift your wire out of the ground where they could become vulnerable to everyday activities and gnawing squirrels or chipmunks.
In mulched gardens or rock gardens or stone creek beds or stone drainage ways: the wire is usually stapled or placed under the mulch or laid under the stone but on top of the soil. We do this so you can locate it easily before you commence future digging.
Your wire may not be deep enough to prevent damage from lawn aeration, yard maintenance equipment (lawn mowers are safe) or shovels. Even verti-cutting or cross-cutting for new seeding or de-thatching can be bad news for your wire where we are shallow around utilities or if we had to hand lay your wire under the sod, or if erosion has occurred or if tree roots have lifted your wire.
If you have intrusive yard work scheduled, such as new drains, phone line or cable line burial, outdoor lighting, aeration, re-edging gardens, new edging gardens, sprinkler system installation, and repair, etc.. on your schedule, you are wise to ask us to locate where your wire is before the work. Call us for an appointment to mark your yard to prevent expensive repair work. We charge for this service, but it costs far less than replacing the line.
I am going to aerate my yard. Should I have the wire located or marked first? And … I am going to verti-cut my yard. Should I locate or mark the wire first?
Yes. And we do charge for this service. However, in the long run, it costs much less to have us mark the wire than to repair it over and over again as knicks in the line corrode and create new breaks in the line in the future. Please call a few days in advance of your work so we have time to efficiently place you on the calendar and to ensure we have time to make it to your home in plenty of time before your work is to be completed.
If you have us mark the yard, and the aeration company cuts or damages it, then you should hold them responsible for reimbursing you for our charges. Our marks on the yard do not guarantee that they will honor the marks, but it gives you the right to demand restitution from them if they screw it up.
We charge to mark your yard before aeration or any other kind of work on your yard. The price depends on the size of the yard (time and materials). In almost every instance it costs less to mark than to fix a fence. The minimum charge to fix a fence from aeration (1 cut, 30 minutes of time) is at least $135. (subject to change at any time). The problem is, sometimes an aeration job will not cut it thru, but damage it in multiple places. These places will eventually fail in a cascading fashion over time. This type of failure ends up requiring multiple repair trips. Each trip will cost at least $135. Those multiple trips usually upset a customer and stress our relationship with them. But we cannot find things that are not CUT all the way thru. Consequently, all we can do is respond to your next requests for service. We ask that you remain patient with us as we gradually work our way thru each repair until it finally quits breaking again someday.
We plan to have our driveway worked on (mud-jacked, replaced, restored) and the fence crosses this area. Should we worry about our wire?
Your concrete contractor can place a PVC conduit under the rebar before he pours concrete and we can then put a wire thru it, or we can put a wire down before he pours without the conduit, or we can do it after the job is done IF there are no fancy edges that you do not want us to cut with a saw.
Perhaps, your best choice if we can time it well is to be there after the concrete is knocked out, but before the new concrete is poured. This is usually only a one hour window.
It costs a little more to do it after the concrete is poured because we have to cut it with our saw, but it is difficult to catch that one hour window of opportunity.
Nobody has been working in my yard. How is it that my wire is cut?
A wire can be nicked or cut with yard aeration, verti-cutting, shovels, “For Sale” signs, tillers, stump grinders, Termite control stations, new driveway installations, shovels and most any other gardening tools. Rodents can chew into a plastic casing and sometimes bite through it. Environmental forces can damage a wire in unexpected ways. One of these forces is expansion or contraction of the ground, forcing concrete slabs in driveways, sidewalks, and stairs to compress and squash the wire so hard that it pinches it in half. Sun can damage and crack the plastic casing (even UV protected plastics will not last), so that moisture can infiltrate and corrode the wire.
Dog fence wire contains a metal conductor. Professionally installed fences usually employ either 14 or 16 AWG Copper or Copper Clad Steel wire. (Either is typically used in the dog fencing industry). The wire is highly conductive and also highly subject to rapid corrosion when open to a wet or corrosive environment.
Tensile strength: Wire can be stretched and twisted. However, eventually, it will break. A wire’s tensile strength when it is new and in perfect condition is different from when it is older and subject to conditions which cause deterioration on the metal conductor in the wire. If too much metal corrodes away, the line may break under much less stretching force than it might have otherwise at the same temperature and pressures of new wire.
Sun exposure to the wire casing: Even UV protected casing will suffer over prolonged exposure. Such damage can be seen as tiny cracks or entire pieces of casing breaking off and exposing raw conductors. This will allow water to penetrate and react with the metal. However, if sun deterioration is occurring, then the wire is probably not in a wet environment, as it is not buried so if the conductor gets wet, it will usually dry with only minimal impact.
Moisture absorbent wire casing: PVC wire casing is not my favorite. PVC cased wire contains micropores that allow water penetration. PVC wire casing is also susceptible to deterioration through exposure to acids in the soil. For these reasons, we do not use PVC cased wire. We only use HDPE or HMWPE wire casings.
Household electrical wire: This type of wire used to be the norm in this industry, but over time it proved to be inappropriate and less desirable than the wire we use today. Household wire, while double cased (The outer case is clear) it damages easily and ultimately degrades from long-term ground contact.
What happens to wire over time?
Time – Conditions constantly change over time. Heat, cold, wet, dry, digging, shaking, movement, shovels, rodents chewing, splices, nicks. All things are possible given enough time.
An intrusive yard job (Aeration, verti-cut, sprinkler system installation, outdoor lighting, cable TV lines, etc.) can cut cleanly through a wire, and other times nick or skin a wire. Our dog fence wire does not heal itself like you or I if we cut our finger or skin our knee. A single nick in a line is bad, as it eventually corrodes given enough time and exposure to moisture in the soil. The oxygen of water binds to the copper and corrosion begins immediately. Eventual corrosion creates a weakness in the wire in that spot. Over time, ground settles then swells again like a big sponge. Expansion puts pressure on a wire and stretches it. Eventually, the stretching wire breaks due to pressures exerted by the pulling forces of the swelling ground around it.
Clean Cuts and Nicks
Worse still, multiple nicks. This sometimes happens in multiple places during the same yard or over multiple jobs in the yard. For instance, lawn aeration, or burying a communications line can nick the line multiple times, and maybe even cut it clean thru a time or two.
Clean cuts in yards with just the right amount of moisture in the ground are relatively easy to find for us. But dry the ground out too much, or put too much moisture in the ground and it gets tricky and takes more time.
Nicks in the line don’t present immediate problems to the system. However, one day, months or years from now, they will begin to fail in a cascading manner. This means that you unplug the fence when the first one fails, then the others may soon fail shortly thereafter. We do not know if the one break is the first of many more to come, or the one and only. Though, with a Volt/Ohm meter, we can generally tell if there are other problems in the yard, such as bad splices. That doesn’t mean we can find the bad splice, only tell that it/they exist.
Wind – Indirectly affects wire because it causes trees to sway
Wind? Yes. Even wind. Wind dries out a yard. When the yard dries out, cracks open in the ground. That causes pressure or pulling forces on a line. As moisture content is lowered, then a yard’s soil is less conductive and a bad splice may cease to carry enough current and a wire break alert can sound.
Wind also exacerbates a bad splice situation when the bad splice is near a tree that can move as the tree sways a little. Gentle swaying rocks the ground in the vicinity of the tree. This slight movement shifts the ground around a tiny break or bad splice. Continuous pulling of the wire just a tiny bit over and over again can cause a splice to separate, or a nick to break or pull and relax, pull and relax. Connect, disconnect, connect, disconnect.
Lightning strikes near enough to the line are a problem as the high voltage and amperage of lightning can blow bad spots out like a fuse gets blown in your car or home.
Another way a nicked line can affect us is that sometimes after a wire pulls apart and breaks, it can also move back together as the ground shrinks and expands, over and over. The close proximity of the two wire ends and the electrical current in the line carried across a short distance (thanks to moisture and sometimes even high conductivity levels of some soils is sufficient to allow the fence to operate again.
Some waterproof and direct burial wire connectors fail over time due to lightning strikes or the waterproof materials drying out or incomplete submersion of the copper wires into the waterproofing connector gel.
Water / Moisture
Moisture causes expansion and contraction of the soil – Think of a sponge on the counter behind your sink that is sometimes dry and shrunken while other times it is wet and full. Imagine a wire in that sponge that under proper conditions will expand to the size of the sponge. However, damage the wire, and it is subject to breaking under the pressure of expansion.
On the other hand, damage on a wire in a dry area may never become an issue. This may happen if a wire is buried in dry sandy or rocky soil. Well-drained soil allows the moisture to drain away so the wire remains relatively drier, slowing corrosion. A wire stapled to a fence post, chewed on by a rodent may also never fail from corrosion. Also, a damaged wire laid on top of a garden may also not corrode as quickly as one under the mulch or in the dirt.
Clay soils hold the moisture longer. Well-drained sandy soils corrode slower than clay soils.
H2O Content of soil aids in the conditions required to cause wire corrosion. Water can also help delay some wire break alerts by conducting electricity thru the moist soils.
Acidity Levels and Conductivity
Some soils are more acidic than others, hurrying the corrosion process.
Another factor to consider is the effects of electrolysis. This is where electrons of dissimilar materials will migrate from an area of high concentration to a lower concentration. In the dog fence world, we recognize this effect and are aware that even a bad splice or open nick or scrape on a wire will fail slowly if there is a steady low voltage energy supplied to the wire.
The Conductivity of soil changes as moisture is added. Some soils are more conductive than others. This happens from dissolved fertilizers containing salts. Any concentration of salt creates a corrosive environment. Aqueous saline solutions flowing by chance to, around and thru the vicinity of exposed conductors create potential for invasion of corrosive moisture and materials to the copper wire. A wire loses electrons to the environment. This causes a wire to thin and break or change to a less conductive state, creating a wire break or wire break alert.
Use of fertilizers – Fertilizers increases the conductivity of soil and aids in Electrolysis. Electrolysis occurs quicker with higher concentrations of electrolytes in the soil.
Soils that receive fertilizers have more metals and electrolytes in the soil. This allows corrosion to occur more quickly. Add moisture (irrigation systems) to the soil, dissolving the salts, and metals into liquid solutions that penetrate a wire nick or bad splice (wrapped in electrical tape), and the corrosion will occur more quickly.
Bad splices are the crux of many service calls. This creates an intermittent situation where the fence will work for a while, then stop, then start, then stop. This happens when an improperly spliced line gets moisture into the splice causing corrosion between the two wires. Corrosion creates resistance and weakness in the line. High resistance causes a wire break alarm to trip, and the weakness of the splice can cause it to pull apart.
When we suspect that the line will fail again because of high Ohm readings, or fluctuating readings caused by bad splices or shifting ground around broken wires, we will inform the homeowner that they will be calling us again. Sometimes that can happen before we can get out of the neighborhood. Other times it takes hours or years.
A succession of breaks is very frustrating for a homeowner. They always want to blame us for not fixing it right the first time. This is why we offer to go back for free to check our work. We expect with 99% certainty that we will find another break or another bad splice that someone else made before us. When we find someone else’s bad splice or another break we charge again for our service.
When wires fail from nicks and bad splices in the wire, a customer can usually count on seeing us multiple times before we can work all of the bad spots out. Each trip will cost the owner money again and again. Those multiple trips usually upset a customer and stress our relationship with them. But we cannot find things that are not CUT all the way thru. Consequently, all we can do is respond to your next requests for service. We ask that you remain patient with us as we gradually work our way thru each repair until it finally quits breaking again someday.
Fact: A fence with a constant low voltage power supply (plugged in and turned on) with a wire/line resistance below the minimum threshold to trigger the wire break alarm (the wire is in good shape and there are no bad splices or open wires exposed to ground) will corrode slower than one with the power supply removed at a higher than optimal resistance. What do I mean by that? If you leave your fence plugged in, the bad splices and nicks corrode slowly. On the other hand, if you unplug an otherwise normally operating fence with nicks and bad splices, the lines are exposed to a lower naturally occurring nominal electrical background of the earth. Unplugged, a wire deteriorates quickly. Thus, a fence left energized, albeit in a state of high resistance will generally not trigger a wire break alert for much longer than one left unplugged.
This theory is important because once a fence fails from one event, by the time we get there to fix it, we often find many old damaged areas that have failed since you placed your call to us for help. Or maybe you waited weeks or months or even years to call us. That’s OK and maybe even a good thing because while you waited to notify us, other spots that were going to fail in a few weeks or months were allowed to fail early and we can fix them all at the same time with fewer service calls and lower overall cost to you. But when it fails again days or weeks later, we always hear the same thing from our customers… “You were here to fix our fence, and it is beeping again.” We hear that you are frustrated. What we also hear is: “You didn’t fix my fence”.