I recently had a turbidity sensor fail at my plant. The lens cover was off of the 90 degree detect window is the only thing I could find wrong. Ours do not have the wipers on them. Would that be something we should consider ordering the ones with wipers but when I tested the sensor all it would say is no sensor found. I had been working perfectly. Are there any kind of rebuild kit or is it just replace the whole sensor?
Depending on the solid content and dirtiness of the sample you may want to consider the sensor with the wiper. It would reduce your cleaning intervals\maintenance significantly and would product more reliable results.
Please also check the chemical compatibility between the sensor and media. There are two body types available for this sensor PVC and SS. The sensor can be repaired. Please contact Hach service center to receive a quotation for the repair.