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Infra-red sensors are normally "dark environment" sensors. In other words, they work best when they cannot see ANY ambient light. The detector you have selected can work adequately in the presence of ambient light.

These detectors are considered "spark" detectors. They only "see" energy emitted in the infra-red spectrum, and characteristic with a carbon fire.

When designing your system, I recommend the following:

1. Take into account the half power cone of vision of the device (don't try to cover more area with a device than recommended by the manufacturer).

2. If your environment includes lots of suspended particulate dust, consider the air purge option for the lenses. If air purge is unworkable for you, monitor the lens surface closely for the first few months of operation to determine the cleaning frequency required.

3. Install test lamps at each detector location. These devices will emit Infra-red radiation when activated, allowing you to prove the devices are working. These should be activated by test activation switches at your controller. You should also have "detector active" LED's at the controller to prove that they are working when testing.

4. You should have a water spray nozzle installed down-conveyor from the detectors. The distance will be calculated based on the conveyor velocity and the time in milliseconds for the water solenoid to open fully from time of detector activation.

5. Install a flow switch in the water line with a flow indicator at the controller. The system is useless if the solenoid has failed. Install a solenoid disconnect switch at the controller, that will place the controller into a trouble state when activated. You can now test the detectors without flowing water. The trouble indicator will remind the operator to re-engage the solenoid when testing is complete.

6. The entire system should be arranged as "non-latching". The system should be able to extinguish a spark and self reset to a "ready and working" condition.

7. I recommend a spark counter be employed. If a given number of sparks are counted in a given time period (say 25 sparks in 1 minute) the system shuts down the conveyor for inspection.