MiniView - Low Cost Turbidity Sensor for Harsh Environments

MiniView was designed as a low cost means to measure turbidity in harsh environments where explosion-proof enclosures are required.

It uses a compact electronics package contained in a Class 1, Division 1, Groups B-D housing connected to an insertion probe with up to 24 feet of optical fiber. The optical sensor can thus be placed at some distance away from the measurement location.

Filter breakthrough
Crystallization monitoring for pharmaceutical manufacturing
Solids loading in slurries
Proven probe technology licensed from Dow Chemical

The insertion probe is manufactured by Guided Wave under a license agreement from Dow Chemical Company under U.S. patent 4,909,588.

The probe works on the principle of backscattered light from several angled fibers pointing into the process liquid (fibers 1, 2 and 3 in the picture above). Guided Wave added a fourth fiber in the center which illuminates the sample stream and the other fibers pick up any backscattered light from particles.

Miniview is a low cost filter breakthrough sensor, but can also be used quantitatively. This shows the correlation between MiniView's mV output and NTU turbidity using AAMCO Clear NTU turbidity standards (Advanced Polymer Systems, Redwood City, CA) over a wide turbidity range.

Using backscattered light, MiniView can also measure solids loading in slurries which would not be possible with transmitted light.

Specifications

Environment	Class 1, Division 2, Groups B-D (with sealed fittings). C1D1 B-D or Eex d IIB (with optional sealed fittings) ISB required for RTD in classified areas
Dimensions	9.2 x 5.6 x 5.2” (23.3 x 14.3 x 13.3 cm) 1.5 x 1.75” (3.8 x 4.4 cm) mounting holes
Temperature Range	10-50 C (non-condensing)
Power Supply	22-26 VDC, 0.2A typical (Supplied with external 110-240VAC, 50-60 Hz power supply and connections for initial laboratory testing)
Outputs	4-20mA analog output for turbidity and temperature (isolated and self-powered; other outputs available) LCD display for answer display
Connectors	SMA connectors for fiber optics
Detector	Silicon
Light Source	630 nm high brightness LED, 100,000 hours lifetime
Precision	+/- 1 mV

Product Brochure