Heavy Duty Back Spillage Detector


The Heavy Duty Back Spillage Detector is designed to prevent spillage of conveyed mineral around transfer points and chutes. The complete transducer comprises of two similar units, one mounted on each side of the conveyor at a point where spillage is likely to occur. The unit is designed to be mounted such that the centre line of the paddle is in line with the edge of the conveyor belt. When the paddle is depressed due to spillage of material, a rotary switch operates within the unit.

Cable entries:

The unit is supplied with one CM 20 20mm cable gland and one 20mm tapped blanked off entry.


As an option a time delay function can be provided which prevents the conveyor from being tripped if the paddle is depressed momentarily by a lump of material dropping off the conveyor.


The Heavy Duty Back Spillage unit is deemed intrinsically safe to the ATEX standard EN 60079-11:2012 Explosive Atmospheres-Part 11:Equipment protection by intrinsic safety ”i” section 5.7 ‘Simple Apparatus’. The switch contacts can be used to switch an intrinsically safe circuit with the following characteristics: Ui max = 50 volts; Ii max = 100mA

Switch Rating:

The Heavy Duty Spillage Detector is fitted with a rotary switch equipped with one normally open and one normally closed contact.

The contact ratings are as follows:

  • 16 Amps 250 volts ac 3 kw
  • 1 Amp 125 volts dc