Smartphone Electric Fence Detector

Electric Fence Detector Off

Anyone who has experienced being shocked by a several thousand volt Electric Fence knows it hurts - really hurts! Daniel Hall envisaged it should be possible to implement some "smart technology" - harnessing the power of a modern smartphone - to detect whether the fence was on or off. With that in mind, Dan engaged Beta Solutions to assist with the development. What resulted was a product which won the Vodafone Innovation in Technology Award at the National Fieldays at Mystery Creek in 2015.

Fence Detective


The Fence Detective company (Danz Zapps) was formed through the frustration of a Northland forestry contractor needing to know the state of an electric fence (ie: On or Off).  When he couldn’t get in touch with the local farmer – and as he braced himself for a 50/50 chance of getting a nasty electric shock – he said to himself, “There’s got to be an easier way to find out".

While many dedicated electric fence meters already exist on the market, many people are not interested in carrying around an additional (and often costly) device. What was needed, was an ability to detect the state of an electric fence using a device that most people already carry with them - a modern smartphone.

New Zealand inventor Dan Hall approached Beta Solutions with the non-trivial task of solving this problem.

Testing an electric fence


At first glance, one might think that due to the impressive capabilities of a modern smartphone, it would be a relatively straightforward exercise to detect an electric fence signal. However, (simply put) smartphones don't come equipped to detect the unique signature of an electric fence pulse, which often ranges between 2-10 thousand volts. What was needed was a innovative and creative solution - which incorporated some advanced signal processing detection algorithms.

Sensing Solution

If a phone is to determine whether or not the fence is On - then the phone firstly has to "sense" the fence's electrical signal. Perhaps the first technical barrier to overcome was devising a sensing solution that would be compatible with the plethora of different smartphones that exist. 

Broadly speaking, in today's market, there are two main camps of smartphone operating systems: 1) Apple's "IOS" operating system & 2) Google's "Android" operating system. NB: To a lesser extent Microsoft (and others) also have smartphone operating systems.

While IOS is designed to operate only on Apple's own devices, the Android operating system is designed to operate on a variety of hardware developed by many different manufacturers (eg: LG, Samsung, Huawei etc). 

After researching several possible sensing concepts , including both internal phone sensor and possible external sensors, one suitable (and innovative) solution emerged. Essentially, the solution involved the novel use of phone's audio port - which are commonplace on almost all phones. In fact, the sensing means were so novel that Danz Zapps were successfully able to patent the concept.


Detection Solution

Once we verified the phone could receive a reliable input signal (radiated from the electric fence), the next step was to process the data and ultimately inform the user whether the fence was On or Off.

We set about implementing an advanced (also patented) software detection algorithm. Essentially, the algorithm consisted of advanced signal processing techniques to filter out unwanted signals and deduced the periodic pulse train (as a result of the fence being On) with a high level of accuracy.  

Additionally, each phone was capable of being calibrated prior to use - in order to extract the optimum levels of performance from the detection algorithm.


Systems Integration and Final Product

Once we completed the development and exhaustive systems integration testing of the software detection algorithm, the computer code was sent to 3rd party specialist App Developers. The App developers were able to incorporate the algorithm and develop the remainder of the App for both Android and IOS operating systems.


The product was commercialised in 2015 with sales continuing to increase to both national and international customers. Moreover, in 2015, the Fence Detector was the recipient of the National Agricultural Fieldays "Vodafone Technology Innovation Award"!

  Checking Fence Detecting fence is off Detecting Fence is On


* All the content in this article, including imagery, has been approved by our client for publication on this website.