Three versions of Live Line Indicators are available to cover the most common system voltages of 750V, 1500V, and 3000V DC. Although usually applied to overhead catenaries they can also be used on “third rail” installations. Proving that the system is de-energised, and can thus be safely earthed, is important to both maintenance staff and system security.
High Voltage DC Live Line Indicators give both visual (high intensity flashing red LED’s) and audible (70 dB) alarm should a conductor under test indicate as live. Each version has a threshold setting of approximately 33% of system voltage, above which the line is deemed to be energised.
The unit is the first armed with the test button which will cause the alarms to activate and upon releasing the button the red LED’s will be replaced by green ones and the audible the alarm will stop. The green condition will remain active for about 5 minutes during which time the unit can be applied to the line under test and if the threshold is exceeded the Warning alarms will again be activated. Pressing the test button also performs a battery check.
A universal “star wheel” adaptor is also available to connect to other operating poles and alternative clamps are available to suit various earthing systems, e.g. buried rail.