JVA ZLM4 - Low Voltage 4 Zone MonitorJVA ZLM4 Low Voltage 4 Zone Monitor * Excluding Battery and Power Supply The ZLM4 is designed to be used by itself or in conjunction with a number of high voltage security electric fence energizers to monitor fence integrity. It places safe, isolated, Extra Low Voltage (ELV) pulses on the monitored wires and alarms on a cut, short to ground or short to high voltage to detect someone tampering with the fence. Each ZLM4 can monitor up to 4 loops of