Sludge-level Detector

Sludge-level Detector

The aluminum and PVC Portable Sludge gun locates the sludge bed in clarifiers and settling tanks by sending bursts of infrared light from a light emitting diode to a photo transistor across a gap of an immersed sensing probe. A solid-state circuit differentiates between liquid or sludge in the gap, ignoring solids suspended in the liquid. A variable-pitch horn on the butt of the gun howls as the probe nears the sludge, with the pitch and volume increasing as the probe passes through the "cloud" above the sludge and into the sludge bed. A thumb-operated sensitivity control adjusts for thick or thin sludges. The sludge level is read from numbered markers on the cable. The standard cable length is 10 meters (33 ft), and extra cable is stored on a spool at the front of the gun. A state-of-the-art pulsed circuit with a 1 percent duty cycle plus a spring-loaded trigger (off) switch provide a year or longer battery life. The weather-proof unit weighs 4-3/4 lbs. Fixed installations for automatic sludge blanket control are also available.