Solving ‘coastal click’

Residential Estate Security Handbook 2016 - Vol 1 Residential Estate (Industry), Perimeter Security, Alarms & Intruder Detection

Coastal click, a phenomena experienced predominantly on electric fence installations along coastal areas, but which can also occur in very dusty areas, is caused by salt or dirt build-up on insulators. This results when there is a dew or light mist in current tracking across the now salty or dirty conductive surface of an insulator and arcing onto a support post. The resultant ‘click, click’, or worse, ‘klack, klack’, aside from being annoying can lead to false alarms being triggered.

Until the 1980s the maximum output voltage of an electric fence energiser was capped at 5000 volts. With the advent of solid state electronics and improved, safer circuity, this cap was later lifted to 10 000 volts. The problem, however, is that insulator design did not keep pace with energiser power output and when steel supports are used, as is the case with most electric security fences, tracking becomes a problem.

The solutions to this problem to date have been to periodically wash down the insulators, which is time consuming, or alternatively to resort to large, bulky, agricultural type insulators which are not attractive around a prestigious estate. Bi-polar fencing is proving to be an attractive solution to this irritating problem and is being increasingly used by many of the country’s top installers.

Bi-polar fencing

The wiring configuration of a conventional electric security fence is generally configured with alternate live and earth return wires. This is done because an intruder wearing rubber soled shoes will be insulated from the ground and thus will not receive a good deterrent shock. It is in fact necessary for an intruder to touch both the live and earth return wires to receive a shock.

So what is bi-polar fencing? On a bi-polar fence a positive pulse is transmitted along one wire and a negative pulse along the next wire. This means that every wire on the fence, with the exception of one true earth wire, is now live and, just as with a conventional electric fence, when both wires are touched the intruder receives the full shock.

The big difference, however, between a bi-polar and a conventional electric fence is that voltage on the wires on a bi-polar fence is half that of the single live wire configuration and this reduction in voltage, while in no way reducing the security provided by the fence, eliminates the tracking and annoying clicking and false alarms.

Nobody can tell the difference between touching the live and earth on a conventional electric fence and the live and earth on a bi-polar fence because the shock is exactly the same. So the net advantage of bi-polar fencing is improved security with all wires being live, all wires being monitored and no annoying coastal click.

Finally, the use of JVA bi-polar energisers, in conjunction with a JVA Windows compatible Perimeter Patrol electric fence software management package, with its optional High Level Integration program (HLI) has become the electric fence management tool of choice among many of the country’s professional fence installers. JVA bi-polar energisers and Perimeter Patrol software can use either hard-wiring, fibre optics, GSM or Wi-Fi for information transmission giving the end-user peace of mind and a comprehensive solution to their perimeter security challenges.

For more information contact Ndlovu Fencing t/a Stafix Electric Fence Centre, +27 (0)33 342 6727, [email protected], www.stafix.co.za



Credit(s)




Share this article:
Share via emailShare via LinkedInPrint this page



Further reading:

Nice launches DC Blue Astute garage door motor
Nice Group South Africa Technews Publishing News & Events Access Control & Identity Management Perimeter Security, Alarms & Intruder Detection
Nice Systems SA has launched the Nice DC Blue Astute, a garage door motor for the South African market featuring a pre-installed lithium-ion battery instead of traditional lead-acid batteries.

Read more...
Smart access for a safer community
neaMetrics Suprema Access Control & Identity Management Residential Estate (Industry) Products & Solutions Commercial (Industry)
Suprema has released its BioEntry W3 facial authentication access control device with multiple authentication options, including RFID cards as well as mobile credentials, designed for durability and resilience.

Read more...
Securing access against unwanted visitors
Intelliguard Access Control & Identity Management Residential Estate (Industry) Products & Solutions
In today's residential estates and complexes, one of the biggest concerns is preventing unauthorised access, while ensuring a smooth and convenient experience for residents and approved visitors.

Read more...
Smart access for a safer community
neaMetrics Suprema Access Control & Identity Management Residential Estate (Industry) Products & Solutions
Suprema's BioEntry W3 integrates AI-powered facial authentication into a sleek design that prioritises security, privacy and user experience, and even allows users to store their facial templates on their mobiles instead of external devices.

Read more...
Effortless and secure visitor management
Secutel Technologies Access Control & Identity Management Residential Estate (Industry)
Secutel Ventures has introduced SecuVisit, an access control solution designed to simplify visitor management while enhancing security. With two innovative components onboard, SecuVisit ensures seamless visitor check-ins anytime, anywhere.

Read more...
Glovent’s SOS Suite triple protects estate residents
News & Events Access Control & Identity Management Residential Estate (Industry)
One hundred and fifty-three years since the world’s first panic button was introduced in New York City, Glovent offers estate residents three different ways of summoning emergency assistance at the touch of a button.

Read more...
Dahua launches 2-wire hybrid video intercom system
Dahua Technology South Africa Smart Home Automation Access Control & Identity Management Residential Estate (Industry)
Dahua Technology has launched a 2-Wire Hybrid Video Intercom System (the Dahua EACH Series) that redefines residential security and communication with its high image quality and easy deployment features.

Read more...
Surveillance on the perimeter
Axis Communications SA Hikvision South Africa Technews Publishing Editor's Choice Perimeter Security, Alarms & Intruder Detection
Cameras have long been a feature in perimeter security, with varying reports of success and failure, often dependent on the cameras’ planning, installation and configuration, as well as their integration with other perimeter solutions and centralised management platforms.

Read more...
Visual verification raises the security game
Technews Publishing Inhep Electronics Holdings Videofied SA Editor's Choice Perimeter Security, Alarms & Intruder Detection
Incorporating alarm signals with live surveillance footage, visual verification enables a human observer in a control room (onsite or offsite) to gain a clear understanding of the situation, thereby facilitating informed decision-making.

Read more...
The AX Hybrid PRO Series offers reliable wired and wireless protection
Hikvision South Africa Editor's Choice Perimeter Security, Alarms & Intruder Detection Products & Solutions
Hikvision has announced the launch of a new AX Hybrid PRO alarm system with innovative Hikvision ‘Speed-X’ transmission technology. This system offers reliable wired protection while delivering expanded flexibility with seamless wireless integration.

Read more...