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  • Avocet Sludge Blanket Monitor

    prices from £2,345.00

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Pulsonic Avocet – Sludge Blanket Monitor

The Avocet Sludge Blanket monitor offers one of the most accurate sludge blanket detectors on the market by utilising extremely high frequency ultrasound (1.1MHz) that can detect the lowest sludge density found in secondary clarifiers whist easily detecting high density sludge in primary clarifiers.

Powerful Signal Processing

Defining sludge blanket interfaces is quite a complex task, especially in secondary algorithms and multiple interface layers can cause confusion. The Avocet utilises a range of powerful processing algorithms that the user can programme to generate the optimum sludge return signal. To aid the user, the Avocet allows the user to view the raw return echoes from the clarifier so he/she can tailor the signal processing algorithms to maximise performance.

In secondary clarifiers sludge, layers are often diffuse and difficult to detect. In such clarifiers the Avocet does the signal processing for you and it decides on what is the strongest sludge return echo by utilising extremely powerful mathematical techniques.

High Frequency Sensor

The ability of an ultrasonic sensor to detect the smallest particles is directly equal to the ultrasonic frequency. At 1.1MHz the Avocet has the highest frequency of any product in the market which enables it to detect the smallest particle size and particularly in secondary clarifier with weal opaque sludge layers, its performance is second to none.

Large Clear Display

The Avocet has a large 5” 240×128 graphics display, that in the run mode, shows and marks the sludge level interface on a vertical graph and shows the status of the instrument parameters.

Air Purge Cleaning

The Avocet uses air purge cleaning that is programmable and controlled via one of its four relays. Air purge is preferred to wiper cleaning which are prone to mechanical failure through wiper seizure and water ingress. Air purging is simple, effective and more reliable.

Click to open: Specification


Measuring Principle Underwater ultrasonic sludge level measurement
Measuring Range 0.6-12 metres (2-39 ft)
Accuracy +/- 0.03m
Resolution 0.003m
Response Rate Fully adjustable
Echo Processing Sophisticated algorhithms using 32 bit Digital Signal Processing
Power Supply 115/230 VAC
Outputs and Communications
Analogue 1 4-20mA output, 750Ω
Digital 4 SPDT programmable relays, 5A @ 230 VAC (2 user programmable, 1 purge control, 1 LOE)
Telemetry (optional) Site specific, range up to 2 miles (3km)
Communication Standard RS232, optional RS485
User Interface 3-button keypad with menu driven programming
Echo Profile Graphical LCD display of raw echo profile
Programming Security Password protected
Data Integrity Non-volatile RAM
Temperature Range (electronics) -20°C to +60°C (-4°F to +140°F)
Outdoor Rating IP65, UL Approved Enclosure with UV Protected Clear Lid
Dimensions 280 x 219 x 156 mm (11.0 x 8.6 x 6.1 inch)
Cable Entry 8 Available for Wall Mount: 1xM12, 1xPG9, 5xM20 bottom row
Mounting 2 Fixed Holes & 1 Hanging Hole, Optional DIN Rail Tabs
Enclosure Material Polycarbonate, flmae resistant to UL94-5V
Weight Approximately 1.4Kg (3 lbs)
Transducer Specifications
Standard Cable Length 20 metres (66 ft), optional custom lengths
Cable Specification Shielded Coax Cable
Maximum Cable Run 50 metres (150 ft)
Temperature Range (Transducer) -40°C to +95°C (-40°F to +200°F)
Dimensions 50mm diameter x 75mm length (2 x 3 inches)
Mounting 1 inch NPT Male Thread
Material PVC Housing, IP68 Rating
Beam Angle & Frequency 6° total, 12. MHz
Cleaning Hose Tail Air Pipe Connector for Air Purge
Cleaning Frequency User-programmable, 1-720 minutes (12 hours)
Weight Approximately 0.5 Kg (1 lbs)