Sludge Interface Detector

Raven SID-20200 Sludge Interface Detector is a portable, handheld instrument designed to accurately measure sludge blanket depth in wastewater treatment applications. Suitable for primary tanks, clarifiers, sedimentation basins, lagoons, and tanks with settled solids, the SID-20200 provides fast, reliable interface detection for process monitoring and control. This model replaces the earlier SID-10200 and incorporates several performance and usability upgrades.

Available with 20, 30, or 50-foot probe and cable lengths, the SID-20200 features a counter roller system that eliminates the need for cable markers and delivers precise depth measurements. The backlit digital display shows sludge interface depth in inches or centimetres, allowing operators to easily document results under all lighting conditions. Adjustable sensitivity ensures reliable detection across a wide range of sludge types.

The detector uses an infrared sensor probe connected by a strain-relieved signal cable, with waterproof protection rated IP68 up to 50 feet, while the handheld unit is housed in an IP66 weather-resistant case. Audible and visual indicators confirm interface detection, and a low battery indicator helps prevent downtime in the field.

Replacement probe and cable assemblies are available for ongoing maintenance, allowing the instrument to remain in service for years with straightforward upkeep. Built in the USA, the SID-20200 is a dependable solution for accurate sludge blanket measurement in demanding environments.

Features

• Available with 20 ft, 30 ft, or 50 ft probe and cable lengths

• Accurately determines sludge blanket solid/liquid interface depth

• Counter roller system provides exact measurements without cable markers

• Digital display shows depth in inches or centimeters

• Adjustable sensitivity for varying sludge conditions

• Backlit display for low-light and nighttime use

• Audible horn with on/off control for interface detection

• Low battery indicator for reliable field operation

• IP66 weather-resistant case for harsh environments

• IP68 waterproof probe and cable rated up to 50 ft (15 m)

• Infrared sensor probe with strain-relieved signal cable

• Replacement probe and cable assemblies available
  

Documentation
Brochure
Probe Replacement

FAQ

Is this the same as a “sludge blanket detector”?
Yes. Operators commonly use “sludge interface detector” and “sludge blanket detector” interchangeably. The SID-20200 detects the solid/liquid interface so you can record blanket depth.

What tanks can I use it in?
Primary clarifiers, secondary clarifiers (where applicable), sedimentation basins, lagoons, and most settling tanks with a defined interface.

Is the SID-20200 the current model?
Yes—Raven states the SID-20200 replaces the SID-10200.

Does it show depth in metric?
Yes. The display can show inches or centimeters.

How do I pick 20 ft vs 30 ft vs 50 ft?
Choose based on tank depth + how far you stand from the access point/handrail. When in doubt, 30 ft is the most versatile option.

Can I replace just the probe/cable?
Yes—replacement probe/cable assemblies are available.

Is it rugged enough for field use?
The handheld unit is listed as IP66, and the probe/cable is IP68.

Does it make noise when it hits the interface?
Yes—there’s an audible horn plus visual indication.

Do I need calibration?
For typical process control trending, operators focus on repeatable technique and consistent measurement points. (If you want, add an internal SOP PDF download to strengthen trust.)

Is this for continuous monitoring?
No—this is a portable spot-check tool. For continuous blanket monitoring, plants typically use fixed ultrasonic/sonar blanket monitors.

Do you ship from Canada?
Ships from our Ontario warehouse with Canadian checkout (no brokerage surprises).