JVA ZM20 - 20 Sector Monitor* Excluding Battery and Power Supply The JVA ZM20 are advanced security electric fence monitoring systems, enabling the partitioning of an electric security fence into 20 programmable sectors. This gives greater accuracy in detecting the locality of a fault on the fence line which in turn allows for quicker targeted responses and or better camera positioning. The system is ideal when energizer placement in the field is not always possible. An