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Parmak Frequently Asked Questions

2.Q.What does low impedance mean?

A.In non-technical terms, low impedance means the fence charger is designed to effectively shock through vegetation and other foreign materials contacting the charged wire. Vegetation such as grass, weeds, vines, etc., contacting the charged wire tend to impede or stop the flow of electricity by "grounding out" the fence. This is a common problem which exists on most electric fence installations.The low impedance fence charger is a solid-state capacitor discharge design and has enough power to force the shock through vegetation. It is recommended that the charged fence wire be kept clean of all vegetation, etc. to ensure maximum performance from your fence charger.

3.Q.Does Parmak Manufacture low impedance models?

A.Yes. The Parmak models DF-SP-LI, EM-200, Mag 12 U.O., Mag 12-SP, HS-100, FM-3, Mark 8, S.E.5, and RM-1 are low impedance, UL listed models. See Parmak`s full line catalog or website for details on these and other top quality Parmak & Baygard electric fence products.

4.Q.Does Parmak sell more than electric fence chargers?

A.Yes. Parmak offers a complete electric fence system including fence insulators, ground rods, fiberglass & poly fence posts, etc.

Baygard by Parmak, the leading brand in temporary fencing, offers a complete line of heavy duty 1/4" electric fence rope, polywire, and polytape in 1/2", 7/8", and 1 1/2" widths. Available in black/yellow or all white. Ideal for temporary pastures and rotational grazing. Super strength and conductivity. Excellent weathering properties. 5 year U/V warranty.

Baygard offers 3 choices in portable wire and tape: Light duty - Pasture Pride, Heavy Duty - Baygard, and Super Heavy Duty - Platinum with its exclusive black and silver color.

Refer to our website or our full line catalog for complete product offering and product specifications.

5.Q.What is a Joule?

A.The joule is defined as a unit of energy used to measure the distance a given weight can be moved in a unit of time or the amount of heat produced in a resistor by electrical current. The joule is commonly described as one watt second. The joule does not measure the effectiveness or safety of electric shock.

6.Q.How does the joule relate to the performance of an electric fence charger?

A.It doesn`t. It would take a lengthy discussion to explain all of the different factors which make an electric fence effective and safe. The joule does not measure the effectiveness or safety of electric shock.

Two easily measured factors determine fence charger performance. Guard voltage and shock current. Safety dictates that the amount of shock current, on time (the amount of time the shock is on the wire) and pulse rate be held within strict tolerances established by recognized safety agencies such as Underwriters Laboratory (U/L) and Canadian Standards Assoc. (CSA). The value expressed in the joule does not decode to the user the effectiveness of a shock.

What controls livestock is voltage and current. You must have voltage in order to force electricity through the conductor (fence wire) as well as vegetation touching the fence, etc., and you must have current in order for the livestock to feel the shock.

The most effective fence charger will have the highest, safest power (voltage and current) possible with the shortest on-time, thereby allowing the fence charger to develop a shock which is more effective and at the same time is safe to use.

Example of how misleading the Joule rating is: The Parmak model Pet Gard is a continuous current, non-pulsing type charger designed for very small animals in backyards, gardens, etc. Using the joule rating (Voltage x Amps x Time) the Pet Gard (PG-50), because it is a continuous current fence charger, would have an unlimited joule ratingmaking it the most powerful fence charger, which it is not.

In summary, it is important to point out that Underwriters Laboratories (U/L) or CanadianStandard Assoc., (CSA) do not recognize the joule as a measurement when applied to electric fence chargers.

7.Q.What is Stored Joules?

A.The term "Stored Joules" refers the the amount of energy stored in the fence charger capacitor.

Low impedance fence chargers are equipped with one or more capacitors which store energy until that energy is released to the fence wire through the the fence charger`s output circuitry.

8.Q.Is the amount of Stored Joules (energy) the same amount of joules produced on the fence wire?

A.NO. It is important to know that the amount of Joules produced on the fence wire is much less than the amount of stored Joules.

As an example, a fence charger that claims to have 15 stored Joules may only produce 2 Joules on the fence wire. The loss of energy between stored Joules and the amount of Joules actually produced on the fence wire is caused by the loss of energy within the discharge circuitry of the fence charger. Poorly designed fence chargers can lose up to 90% of the stored Joules resulting in substantially reduced shock on the fence wire.

Knowing the stored Joules of any fence charger is useless information and can not be relied on to determine the shock power on the fence wire.

11.Q.Why are AC models damaged by lightning more often than battery operated models?

A.Battery operated fence chargers are not connected to AC power lines. Most lightning damage to AC powered fence controllers comes in through the AC power line. The lightning may actually strike a long distance away from the fence charger but is transmitted through the power line and will damage equipment connected to power lines, such as televisions, stereos, fence chargers etc. Parmak AC powered fence chargers are equipped with lightning arresters and a 1 amp fuse (model HS-100 has no external fuses) on the AC line. These lightning arresters help to eliminate much of the lightning damage, however, it is impossible to stop lightning damage100%. It is recommended whenever possible that the fence charger be disconnected from the AC outlet during electrical storms. We also recommend that you plug your AC fence charger into a surge protector (see information on the Parmak Electro-Gard). The surge protector will give additional protection to your fence charger. If a Parmak fence charger is damaged by lightning, it is covered by warranty and the fence charger can be returned for service.

When using an AC operated fence charger, we recommend using the Parmak Electro-Gard lightning protector for increased protection of your AC fence charger from lightning damage.

12.Q.Why is U/L listing important?

A.An electric fence charger is different from any other electrical appliance. All other electrical appliances are designed not to shock where an electric fence charger is designed to shock. That shock must be effective and at the same time safe. The maximum safe limit for electrical shock is defined by International Standards. In North America (U.S. and Canada) there are two accepted safety agencies for electric fence chargers, Underwriters Laboratories (U/L) and Canadian Standards Association (CSA). Parmak elecrtic fence chargers are listed by both agencies. The continuous inspections at the factory by both U/L and CSA insures that Parmak fence chargers comply with both electrical shock and fire safety standards. It is important that the fence charger you use be U/L or CSA listed because this is your assurance that the fence charger has been thoroughly tested and is safe to use. NOTE: There are fence chargers on the market which are not U/L or CSA listed and are potentially dangerous to use.

13.Q.What type of fuses are used in Parmak fence chargers?

A.All AC models use 1 amp fuses. These fuses are designed to help protect the fence charger against lightning and poor ground damage. When replacing fuses, use (3AG) 1 AMP fuse only.  Do not use slow blow type fuses or any fuse rated higher than 1 AMP, doing so will damage the fence charger and void all warranties.

14.Q.What do the performance meters do?

A.The Parmak models Mag-12-U.O., Mag-12-SP, DF-SP-LI, M-8, S.E.5, and RM-1 are equipped with exclusive performance meter. This meter tells the customer the exact condition of fence at all times. The meter takes the guess-work out of electric fencing and eliminates a lot of unnecessaryreturns. The Mag-12-UO, Mag-12-SP, and DF-SP-LI have an analog meter and the Mark 8, S.E.5, an RM-1 have a digital meter.

The meter can also be used in troubleshooting. Pease refer to question 15 below for more information on troubleshooting using the built in meters.

16.Q.Recommendations on which fence charger to use under various needs.

A.The application of electric fence varies widely from fencing small pets such as cats, dogs to domestic livestock, cattle, horses, hogs, sheep to fencing wild animals, deer, bear, (elephants in Africa), etc. The model you choose will depend on the fence construction and the animals you are controlling.

Parmak offers ten (10) models which will meet any fencing requirement. We make the following suggestions on our most popular models:

MODEL DF-SP-LI (BEST) This is a six volt, solar powered model designed to be used on clear weed free fences. The DF-SP-LI is low impedance and will shock through a light amount of wet weeds and brush. It is designed for small to medium size pastures and is ideal for hogs, cattle and horses.

Model MAG-12-U.O. (BEST) MAG-12-SP (BEST) These are 12 volt models designed for medium to large pastures. Both models are low impedance and will shock through weeds and brush and are ideal for cattle, horses, hogs, sheep, deer, etc. The MAG-12-U.O. and MAG-12-SP can be used to fence large animals and larger pastures. The MAG-12-SP is solar powered.

Model HS-100 (110v-120v AC) and EM-200 (12v battery) Safe, effective, shock. Works well with small to large sized animals including dogs or horses. UL Listed (U.S. & Canada) Shocks through a light amount of weeds & brush, advanced solid-state circuitry. Quick, easy installation. Dual flashing operating light(red/green) on the HS-100 and single operating light on the EM-200. Rugged ABS housing. Ideal for small to medium pastures.


Model FM-3 (110v-120v AC) (GOOD) This AC model is for small to medium size pastures and will shock through a medium amount ofweeds, brush, etc. The FM-3 is ideal for hogs, cattle and horses. The FM-3 is not recommended for sheep or deer fences.

Model MARK 8 (BETTER) Model S.E.5 (BEST) Model RM-1
These are the top AC models for the medium and larger fences. Ideal for all livestock or deer fences. The S.E.5 and RM-1 are the best choice for high tensile fences and can charge over 50 miles (S.E.5) and 100 miles (RM-1). The M8, S.E.5, and RM-1 will shock through medium to heavy vegetation. The S.E.5 and RM-1 are also excellent for sheep, deer, or predator fences.