1) Security - Security electric fences are solutions designed to keep human intruders at bay. These are sophisticated systems and generally more expensive than agricultural electric fences. Key difference is the type of Energizer used. Energizers used in security fences have inbuilt voltage monitoring and alarm system. They are capable of interfacing with software, Gsm modules, and third party alarm systems. As a rule of thumb the spacing between wires for Security electric fences is fixed at 100 mm or 4 inches. For security electric fences, detection of intrusion attempts is of highest importance and hence the entire fence is wired in series and the boundary length is divided into several zones for better detection. Different types of security fences are:
a) Wall top: Here six or more electrified lines are installed on top of wall. Poles are fixed at a maximum distance of 3 m from each other. Standard heights over wall surface are
i) 2 feet or 625 mm(6 lines),
ii) 2.7 feet or 825 mm (8 lines),
iii) 3.3 feet or 1025 mm(10 lines) and
iv) 4 feet or (1225 mm)
Wall top electric fences are a good, economical, aesthetic and more effective alternative of barbed wire and concertina coils.
b) Free Standing: Free standing or ground up electric fences is generally a second line of defence after a wall or other fence system. However, there are direct freestanding installations also. Freestanding electric fence generally has strong strain points and strong corners, as they take the entire load of wires and intermediate poles are comparatively lighter. Cement foundation is required only for the Strain and corner poles, intermediates are directly hammered inside. Standard heights over ground level are:
i) Eight feet or 2425 mm (24 lines)
ii) 10 feet or 3025 mm (30 lines)
c) Combined Fences: these are combination of two fence types like chain link fence + electric fence, industrial weldmesh fence + electric fence, 358(anticlimb) fence + electric fence. This type of fence has many advantages over systems discussed above as you get the desired strong physical demarcation as the wall, yet it is see through and you get detection and deterrence by virtue of electric fence. Electric fence is either installed on top of the fence or from ground level up and continuing above the fence but taking support of fence poles. Such fences are quicker, economical and more secure than building a wall.
2) Agriculture: Here the application is to stop animals from crossing over. This works both ways; it keeps animals meant to be kept outside one's premise like wild animals, stray cattle etc. outside and those meant to be contained inside one's premise like pets, cattle, sheep etc. inside. However, the former application is more popular in India. Agricultural fences are optimized for cost and solution is designed to keep a set of animals at bay. That is why there are more wires at bottom(less spacing) to stop the infamous wild pigs, porcupines, dogs poultry etc. and few wires as we move upwards to stop bigger animals like cattle, deers, elephants etc.