Fuel Oil Leak
Detection Systems

Three or Four Zone Oil Leak Detection Alarm Type ODS4-3

Three and Four zone fuel oil Leak alarm with audible warning, Large Alpha numeric Display, Alarm Mute and display back light On, push buttons and alarm relay for onward signalling.

Two types of leak sensors are available, one for internal use only, the other for both internal and external use.

Optional Equipment
Beacon Sounder - for remote alarm indication SMS Text Messaging System - sends a text to up to 3 users Water Shut Off Valve - to stop a leak at it's source 12 Hour Battery Backup

Sized at 180mm wide x 180mm high x 80mm deep, the ODS4-3 has been designed to monitor four independent zones for fuel oil leaks including but not limited too, Diesel, Heating and Hydraulic oils via optical sensors.

With no oil leaks being detected, the screen will display “The System is Clear No Alarms to Display”. When one of the detection sensor comes into contact with oil, the audible warning device will sound, the common alarm relay will close and the display will change to advise the sensor zone i.e. “OIL LEAK DETECTED AT ZONE 1”. A mute “Mute Alarm” button is provided to cancel the audible warning. The system will remain in this state until the Oil has been removed from the sensor. If more than one zone detects an oil leak at the same time, the display will latch on to the lowest numbered zone. Once muted, the display will latch onto the next zone in alarm and start the audible warning devise again requiring the “Mute Alarm” button to be pressed again. When the system is clear from alarms, the screen back light will turn off. Once the unit detects an oil leak the back light it will automatically turn on and remain on until the leak has been cleared. A “Screen Light” push button has been provided to allow the back light to be turned on when the system has no alarms to report and will automatically turn off again after five minutes.

The sensors mode of operation is the principle of total internal reflection. An LED and phototransistor are housed in a plastic (Polysulfone) dome. When no liquid is present, light from the LED is internally reflected from the dome to the photo-transistor. When a liquid covers the dome, the effective refractive index at the dome-oil boundary changes allowing some light from the LED to escape. Thus the amount of light received by the photo-transistor is reduced indicating the presents of a liquid.


  • The unit can be supplied as a 3 or 4 zone system
  • A maximum of two sensors can be fitted to each zone
  • Large back lit alpha numeric display
  • Internal Zone Alarm lamps
  • With the exception of mains power, all terminals are of the plug and socket type
  • On board audible warning device to alert local operators of a problem
  • Alarms latched until Mute operated
  • Common alarm relay contact for onward signalling to a BMS
  • Mains power fault relay contact for onward signalling to a BMS
  • Optional individual zone alarm relay contacts for onward signal to a BMS
  • 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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