July 2010 Editor's Picks: Products from Gems Sensors and Controls and Telstar

Gems Sensors and Controls
Flow sensors offer visual indication
The RotorFlow RFO fluid-flow sensors from Gems Sensors and Controls (Plainville, CT) provide a pulsed 4.5–24-V output that is proportional to the rate of flow. The direct-current output can be integrated into most digital logic units easily. The sensors include a highly visible paddlewheel that provides verification that fluids are moving.

As liquid passes through the unit’s body, a magnetic rotor spins at a rate proportional to the flow rate. The magnetic fields turning with the rotor excite a static Hall Effect sensor located in the body and generate a series of voltage pulses. Digital rate meters, totalizers, and other electronic controllers then use the output signal.

The RotorFlow sensors are available in port sizes of 0.25 to 1 in. and monitor fluids with flow rates ranging from 0.1 to 60 GPM. The units are appropriate for applications such as water purification, dispensing systems, chemical metering, and chillers and heat exchangers.

Telstar
Biosafety cabinet protects operators
Telstar’s (Terrassa, Spain) CytoUltra biosafety cabinet is designed to protect operators from cytotoxic and hazardous products that contain small amounts of volatile chemicals. The unit produces laminar airflow and incorporates three stages of high-efficiency particulate-air filtration. Operators control the device through microprocessor electronics. The unit has two independent controls with dedicated fans for the laminar flow and the exhaust fan, each of which is regulated by a dedicated speed probe. The cabinet’s sash is a 20-cm opening, and its sloped glass door is moved electronically.

The unit’s dedicated fan creates an inflow of more than 0.5 m/s. The inflow speed and laminar flow can be adjusted to different set points if required. The inflow and the device’s multistage filtration help shield operators from hazardous materials. Testing has shown that the CytoUltra device protects operators from 20-nm particles. The cabinet is appropriate for pharmaceutical manufacturing processes.