Published 18-03-2021
| Article appears in April 2021 Issue

Thermal Flow Switch keeps it clean in demanding processes

The FLT93C Flow Switch monitors the process cleaning solution’s minimum liquid flow rate to ensure it is maintained during the entire cleaning process runtime.

With its stainless steel wetted materials and standard 20Ra finish, the sanitary FLT93C Thermal Flow Switch helps assure continuous liquid flow rate in cleaning systems.

Available in either mechanical polish or electro-polish finishing, the FLT93C supports both skid-mount and stationary clean-in-place (CIP) systems. The primary purpose of these systems is to ensure all process piping and equipment is thoroughly cleaned per ASME BPE standards.

Available from AMS Instrumentation & Calibration, the FLT93C Flow Switch monitors the process cleaning solution’s minimum liquid flow rate to ensure it is maintained during the entire cleaning process runtime.

Operating over a wide liquid flow range of 0.003 to 0.9 mps, the FLT93C Flow Switch offers excellent accuracy of ± 0.5% reading or ± 0.012 mps.

Designed with unique temperature compensation technology, the FLT93C Flow Switch is the industry’s only thermal switch that ensures set point accuracy for process temperatures that can vary up to ±37.8°C.

It is easily field-configured or factory preset, providing unparalleled flexibility, accuracy and stability for all multiple process sensing and switching requirements.

The FLT93C Flow Switch is suitable for 19.05 to 101.6 mm sanitary tubing process lines, and it connects with a secure tri-clamp fitting for easy removal for inspection and servicing.

In addition to CIP systems, other pharmaceutical uses of the FLT93C Flow Switch include compendial water systems (WFI, PW and HPW) and solution preparation systems (buffer solution). Special options are available for applications requiring more corrosion resistant, wetted materials such as Hastelloy C and Class 1, Div 1 and 2 hazardous areas.

The FLT93 Series Switch is a dual-function instrument that indicates both flow and temperature, and/or level sensing in a single device. Dual 6A relay outputs are standard and are independently configurable to flow, level or temperature.

Based on FCI’s thermal dispersion expertise, the unique sensor technology of the FLT93 Series Switches, combined with FlexSwitch temperature-compensation circuitry, introduces unparalleled performance capabilities:

One standardised, field-configurable FLT93 FlexSwitch control circuit satisfies virtually any combination of application requirements. FCI’s advanced FlexSwitch technology can be packaged in integral or remote configurations for installation flexibility.

The FLT93C Switch beats the heat, too. It is available with a choice of sensors including one that is suitable for process temperatures up to 176.67°C and one that is suitable for temperatures up to 260°C. Hazardous approvals available for the FLT93C Switch include ATEX and EAC/TRCU.

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