New dual alarm flow switch providing pump protection


MS Instrumentation and Calibration announces the release of a new flow switch from Fluid Components International (FCI) designed to provide a reliable early warning alert against potential pump problems in process industries.

Many process industries depend on pumps to move process fluids and keep cooling systems up and running. Problems such as system variable demand, leaks or clogs can cause dry running conditions, damaging the pump’s seals or bearings, and resulting in expensive repair, overhauls or even full replacement.

Engineers responsible for optimising the uptime of process flow networks in chemical plants, electric power generation, food and beverage industries, oil and gas as well as municipal water systems can use the new FLT93 flow switch to get a reliable early warning alert to the potential of dry running conditions, cavitation and other pump issues that can lead to emergency shutdowns, service interruptions and unplanned costly maintenance.

Designed to monitor the flow and temperature of liquids, gases, slurries and more, FCI’s dual alarm FLT93 flow switches are ideal for wet/dry detection in pumps, where sudden, unexpected reductions in media flow rates can leave pumps vulnerable to over-heating conditions that shut down process lines and require troubleshooting and expensive repairs.

Featuring a no-moving parts design, the FLT93 flow switch offers robust pump protection with its dual alarm capability.

With Alarm 1, the switch will detect a low flow situation anywhere between 0.003 to 0.9 MPS (metres per second). This low flow alarm can be regarded as a pre-warning signal for the control system or operator, who can then decide to keep the pump running or shut it down.

Alarm 2 will be triggered when the feed line to the pump is running dry, providing an alert to the operator to shut down the pump immediately because the bearings now see gas instead of a liquid as a heat transfer media, causing the temperature of the bearings to rise very fast. Using a flow switch prevents permanent damage to the pump’s bearings that can otherwise require a complete overhaul of the pump.

The advanced FLT93 flow switch is a dual-function instrument that indicates flow and temperature, and/or level sensing in a single device. Dual 6A relay outputs are standard and assignable to flow, level or temperature. The FLT93 switch can be specified in either insertion or inline styles for pipe or tube installation.

The rugged FLT93 switch is hydrostatically proof pressure tested to 240 bar (g) at 21°C. De-rated with temperature, the maximum operation service recommended is 162 bar (g) at 260°C. Higher ratings are available with special construction and test certification. Agency approvals include FM, ATEX, CSA, CRN and CE.

FCI’s versatile FLT93 flow switches are ideal for applications in demanding hazardous process industries, and also used extensively with or without SIL2 certification in a wide variety of applications in the food and beverage, mining and milling, pulp and paper, pharmaceutical, and water and wastewater treatment among many more.