Water Leak
Detection Systems

Three or Four Zone Water Leak Detection Alarm Type LD4-2 & LD4-2V

Designed to raise an alarm when water touches the leak detection cable or spot probes. The unit can be factory configured as a three or four zone system and comes as standard with an audible warning device, large back lit character display, internal alarm and fault indicator lamps, mute alarm push button, alarm and fault relays for onward signalling, optional battery backup, beacon and SMS text messaging.  

The LD4-2V units can be supplied with water shutdown valve control, a shutdown valve override system and internal shutdown valve “closed” lamps.

Optional Equipment
Beacon Sounder - for remote alarm indication Water Leak Detection Cable - to detect a leak anywhere along it's length Water Leak Detection Spot Probe Water Shut Off Valve - to stop a leak at it's source SMS Text Messaging System - sends a text to up to 3 users 12 Hour Battery Backup Repeat Alarm Unit Type SCA

Sized at 180mm wide x 180mm high x 80mm deep, the LD4-2 & LD4-2V has been designed to monitor three or four independent zones in critical areas for water leaks via linier detection cables or spot sensors. Any number of spot sensors or a maximum of 50 metres of linier water detection cable can be connected to each zone.

The unit comes as standard with monitoring for sensor disconnection / damage to any or all of the four zones that includes both the interconnecting as well as water detection cable / sensor. Any disconnection of any detection cable or sensor from the controller will instigate a “Disconnected” alarm. The LD4-2V systems are provided with individual zone water shutdown valve control or if required, common water shutdown valve control. The LD4-2V is also supplied with internal valve “closed” indication lamps and a shutdown valve override system that can be used to turn on the water whilst waiting for the detection cable to dry out. The unit contains an audible warning device, optional remote beacon or beacon sounder output, Mute push button, and volt free contacts for onward signalling. Unlike other water detection units on the market, the LD range from CMR electrical uses a bi-directional (AC) signal within the sensors.

Using alternating current stops electrolysis which causes the sensors to disintegrate leaving the system unable to detect water. The use of alternating current also allows the sensors to be continually monitored even when submersed in water. This allows the system to self reset after water has been removed for the sensor and no further action to reinstate or reset the system is required from the operator.


  • The unit can be supplied as a 3 or 4 zone system
  • Large back lit alpha numeric display
  • Internal Zone Alarm and Fault lamps
  • With the exception of mains power, all terminals are of the plug and socket type
  • Bi-directional DC signal in the sensors to stop electrolyses and polarisation
  • Individual Zone sensitivity adjustment allowing any zone to be set for high to low sensitivity
  • Monitoring of each zone cable and sensor to ensure continuity and integrity
  • On board audible warning device to alert local operators of a problem
  • Alarms latched until Mute operated to give indication of transient water leaks
  • Zone signal isolation to stop multiple alarms due to sensors coming into contact with earth
  • Common alarm relay contact for onward signalling to a BMS
  • Common cable Fault and Mains power fault relay contact for onward signalling to a BMS
  • Optional water shutoff valve control with internal valve closed lights
  • Optional individual zone alarm relay contacts for onward signal to a BMS
  • Optional zone alarm water shutoff valves to turn off the water source when a leak is detected
  • Optional alarm output to a flashing Beacon
  • Optional alarm output to a flashing Beacon and Mutable Sounder
  • Optional SMS text messaging to two phone numbers
  • Optional battery backup

Data Sheet

Installation Manual

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