Sequoia Scientific FlowControl-Sub - Microprocessor-Controlled Fully Submersible 3-Way Valve System
FlowControl-Sub is a microprocessor-controlled fully submersible 3-way valve system for use in flow-through applications on profiling platforms such as for example CTD’s or profiling floats.
During profiling, the system diverts ambient water through a cartridge filter on either the up- or downcast. When the bottom of the profile has been reached, the system switches so that non-filtered water is measured. The profiles of filtered and unfiltered measurements allow for high-accuracy differential measurements of particle properties, for example absorption, in the entire profile.
- Pinch valve design for full-port flow and easy replacement of fouled tubing
- Rapid transition of valve state (~1 s)
- Auxiliary inputs for analog sensors and Hall Effect volumetric flow sensors (paddlewheel or turbine) [under development]
- Flexible configuration of valve operation for scheduled or profiling operation, as well as start and stop conditions
- Continuous output and internal logging of valve state and depth
Mechanical and Environmental
- Dimensions: 15.625″ (39.7 cm) L x 3.95″ (10.0 cm) diameter (max)
- Weight: 6.6 lb (3.0 kg) in air
- Depth rating: 500 m
- Materials: Black-anodized aluminum pressure case, stainless steel shaft and pinching lever arms, Teflon tubing rollers, acetal resin hold down block
- Tubing: Designed for Norprene A-60-G 0.5″ ID / 0.75″ OD (US Plastic part # 054282)
Electrical and Sampling
- Input power: 12-24 VDC
- Current Draw @ 12VDC: 25 mA / 40 mA / 1.2 A / 2.1 A when idling / sampling w/o auxiliary sensors / switching valve / valve motor stalled
- Serial Output: RS-232, 19200 baud, 8N1.
- Bulkhead connector: Teledyne Impulse part MCBH-5-MP
- Sample rate: 1 Hz
- Valve switch time: 1 s
- Pressure sensor: 0-750 psi @ 16 bit resolution (~1 cm resolution, 0.2% full scale accuracy)
- Thermistor: 16-bit resolution