Amp: Unit of current. Watts divided by voltage.
Current: The current and the duration and rate of its flow that causes the shock. Increasing voltage increases current. Current decreases as resistance increases.
AC current: Alternating current as from the mains power supply.
DC current: Direct current from batteries.
Capacitance: Ability to store a charge of electricity.
Capacitor: Stores electrical charges and pulse energy which builds up in the capacitor and is released by the SCR switch into the fence at approximately one per second.
Electrolysis: Corrosion which occurs when different metals are connected in a wet environment such as with electrical connections on a fence line.
Impedance: Combination of resistance, inductance, frequency, and capacitance (sometimes called AC resistance).
Induction: Power transfer without contact. For example charging “dead” or neutral fence wires which run parallel to live ones.
Insulator: Material across which an electric current will not flow.
Joule: Unit of energy. Watt x seconds. The measure of “kick” of a fence pulse.
Leakage: Conductance from the fence line to ground, caused by poor insulators, shorts and growth on the wires.
Measurements:
- 500 ohms (2mS) – the maximum a human or animal can conduct in the worst conditions, eg with feet and hands in salt water.
- 5,000 ohms (0.2mS) – the equivalent of a cow touching an electric fence.
Outrigger: Electrified wire attached to a conventional fence supported so it is away from the fence.
Power consumption: Electricity consumption does not increase with leakage on the fence line, because most energisers operate on maximum all the time and the VDRs absorb the unused surplus.
Rectifier: Converts AC to DC.
S.C.R.: Silicon controlled rectifier which is a transistorised pulse switch.
Siemens: Unit of conductance, leakage or load. Reciprocal of ohm. 1 Siemens = 1 ohm, 1 millisiemens (mS) = 1000 ohms.
VDR: Voltage dependent resistor. Prevents voltage of more than 5000 volts from leaving the unit by short circuiting the excess voltage.
Volt: Unit of electrical pressure which causes the current to flow. Voltage + current x resistance.
Watt: Unit of power, both electrical and mechanical. 746 watts = 1horse power.
CONVENTIONAL FENCING
Angle post: Post placed where a fence changes direction. Needs extra support by stays and tie-backs.
Auger: Tool for boring holes in timber or for boring post holes in the ground for fence posts.
Boundary fence: Definition under the Fencing Act.
A substantial post, batten and wire fence, having not less than seven wires, not more than two of the wires being barbed, barbed wires to be placed in a position agreed upon by the persons interested, or to be omitted if those persons agree: the posts to be of durable timber, metal, stone, or reinforced concrete, and not more than 5.03m apart, and securely rammed and, in hollows or where subject to lifting through the strainof the wires to be securely footed, or stayed with wirep; the battens to be of durable timber or metal, evenly spaced, and not less than four in each space between the posts; the wires to be galvanised and not lighter than No 8 gauge; the barbed wire to have barbs spaced 0.15m apart, and to be galvanised; the bottom wire to be not more than 0.12m from the ground; the three bottom wires to be not more than 0.12m from the ground, the three bottom wires to be not more than 0.12m apart; and the top wire to be not less than 1.14m from the ground; all wires to be strained tightly and fastened to or let through the battens and posts to provide a tight, durable, stock-proof fence. In practice a boundary fence can be modified by agreement of the parties involved.
Other Rural Fence Definitions under NZ Fencing Act 1978
Seven or 8 wire Fence
A substantial wire fence, having 7 or 8 wires properly strained, with up to 2 of these wires as galvanised barbed wire, or with 1 galvanised barbed wire and a top rail; barbed wires to be placed in a position agreed upon by the persons interested, or to be omitted if those persons agree; the posts to be of durable timber, metal, or reinforced concrete, and not more than 5m apart, and securely rammed and, in hollows or where subject to lifting through the strain of the wire, to be securely footed, or stayed with wire; the battens (droppers) to be affixed to the wires and of durable timber, metal or plastic, evenly spaced, and not fewer than 3 between posts; the wires to be galvanised and of 2.5mm high tensile steel or 4mm steel or its equivalent; the bottom wire to be not more than 125mm from the ground, the next 3 wires to be not more than 125mm apart; and the top wire or rail to be not less than 1m from the ground.
Nine or 10 wire Fence
A substantial wire fence having 9 or 10 wires properly strained, with or without battens (droppers) or lacing affixed to the wires between the posts or standards; the posts or standards to be durable timber, metal, or reinforced concrete, well and substantially erected, and not more than 5m apart, the top wire not to be less than 1m from the ground surface, the wires to be galvanised, and of 2.5mm high tensile steel or 4mm steel, or its equivalent, the space between the ground and the bottom wire not to exceed 100mm, the bottom 4 wires to be not more than 130mm apart.
Prefabricated (Netting) Fence
A substantial wire netting fence properly strained of a minimum height of 1m; the netting to have at east 7 horizontal wires, and, if necessary, extra wires above or below the netting, one of which may be a galvanised barb wire, all other wires to be galvanised in either 2.5mm high tensile steel or 4mm steel, or its equivalent; the vertical stays of the netting to be galvanised wire, and not more than 305mm apart. Posts or standards to be not more than 5m apart and of durable timber, metal or reinforced concrete, additional battens (droppers) may be installed between the posts if both parties agree; the overall fence to be well and substantially erected.
Batten: Used to keep the wires on a fence at equal distances apart.
Breast plate: Piece of timber placed in the ground that supports the stay or a strainer, angle post or corner post. Sometimes called a stay foot.
Bridge spike: Large nail with square head and shank used to attach the decking to a bridge to the stringers (supports).
Cap rail: Top rail on stock yards used to walk along. Top rail on a wooden fence.
Cattle stop: Device made of spaced bars (steel or concrete) over a pit to prevent stock entering an open gateway.
Chain: Imperial measurement of 22 yards, (now 20 metres) used to measure fencing.
Contract: Arrangement between the farmer and fencer to define the work that has to be done in the erection of a fence.
Crowbar: Steel bar sharpened at one end for making holes in the ground. Also used as general lever to move heavy objects. May be called a pinch bar.
Dead man: Anchor to which a strainer, angle post or corner post is tied back. It is buried firmly in the ground.
Dogs: Same as gudgeon.
Dropper: Same as batten. May be made of steel or light chain. Common term in South Island and Australia.
Fence laying: Delivering material to the fence line and laying them out before work starts.
Fence line: The line where the fence has to be erected.
Fencing types:
- Deer fence – usually made from netting 1.8m high
- Grass fence – fence made with two low electric wires and grass inbetween
- Pig fence – usually made of wire netting 1.07m high
- Panel fence – made from wooden panels or palings
- Post and rail – make from wooden posts joined by rails
- Wire fence – 7 wires is the legal requirement for a boundary fence. Other fences can have any number of wires
Foots: The plural of foot.
Footings: Same as foot. May describe the material used for the foot, or a foundation for a building.
Fixed foot: Where the foot itself is secured to the post before it is put in the ground.
Fencing pliers: A combination hand tool used to cut and bend wire.
Floodgate: Gate made of battens and wire across a creek that rises and falls with the water level.
Flying fox: Wire between two dead men used to carry fencing material across a gully.
Gate: Structure that closes an entrance.
Gudgeon: The part of the gate hinge assembly that is fixed to the gate post. The hinge straps fit over the gudgeon.
Guide wire: Wire used to define the position of the finished fence. Used to line up the position of each post.
Hinges: Device used to allow the gate to swing – made up of gudgeons and straps.
Hot fence: A traditional fence that has been electrified.
Intermediate post: Post between the strainer posts. May be called line posts.
Jenny: Device for unrolling rolls of wire along a fence line. May be called a spinning jenny or wire spinner.
Knots: Used to join wire. Many types eg figure of 8, reef knot and double loop.
Maul: Large wooden hammer for driving pointed stakes.
Measuring up: Calculating the length of the fence and the materials needed for costing.
Netting: Fencing wire woven into a mesh with varying sized holes.
Peg: Pointed piece of timber used to mark the exact line of the fence.
Pinch bar: Same as crowbar.
Posts: Used to support the wires on a fence. Are described by numbers denoting their diameter.
Post cap: Metal cover for a post to protect it from the weather.
Post driver: Tool or machine for driving pointed posts into the ground.
Post hole: The hole dug in which a post is rammed.
Post hole borer: Machine (hand turned or engine driven) to bore holes in the ground in which to insert posts.
Ram: To consolidate the loose earth around a post.
Rammer: Tool used to ram the loose earth around a post.
Ratchet: Part of a fence strainer to retain the strain while tightening the wires.
Self tapping bolt: Threaded bolt that makes its own threads when screwed into a post.
Standard: A metal post. Common type is the three-sided Waratah standard.
Standard lifter: Lever for pulling standards out of the ground.
Staples: U-shaped and double pointed nails used to fix wires to a wooden post.
Stays: Supports for strainer or angle post.
Stay block: See breastplate.
Stock proof: Describes fence which effectively restrains stock.
Strain: Tension put on fence wires.
Strainer post: Main support post at either end of a fence to which the wires are strained.
Stringer: Main weight-bearing truss in a bridge. Usually made of timber.
Swinging foot: Where the foot is not fixed to the post other than by the foot wire. The foot is rammed separately to the post.
Taranaki gate: Gate made from fence battens and wire pulled tight by a wooden lever.
Tension: The strain put on each wire of the fence.
Tension meter: Device to measure the strain on each wire.
Tie back: See tie wire.
Tie down: See dead man.
Tie wire: Wire that ties the dead man to the post.
Treated post: Post treated with chemical preservative.
Twister: Tool to make a twitch.
Twitch: Twisted tie-wire made from two or more strands.
Twitch stick: Twister made from wood or steel.
Twitch wire: See tie wire.
Wire: There are many kinds of wire, eg plain, high tensile, number 8 and barbed.
Wire spinner: See jenny.
Wire strainer: Device to tighten wires on a fence.
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