700-453 LDM-621-DDL

The module is designed to monitor a length of Digital Line-ar Heat Detection Cable (LHDC) for both fire condition and fault status (open circuit). The unit is designed such that it may be configured to operate in a two wire mode that emulates the operation of conventional heat detectors. The unit may therefore be directly interfaced with fire control panels by connection to fire zone trigger circuits or addressable interfaces. The DDL has a 3½ digit LCD which activates on fire condition and displays the distance into the zone the alarm has occurred. Digital LHDC may be employed in lengths up to 2km (1999m). The unit has an adjustment to accommodate interposing cables. Signalling of fire and fault status by means of VFC may be realised when a separate supply is employed. A 4mA to 20mA instrumentation current loop output is provided for connection to PLCs etc.