Flow Switches

During the past few years it's generally been accepted that analogue float type flow meters cannot always provide an accurate indication of performance when used in low flow rate applications. But now, thanks to R&D engineers from SMC, the world's leading automation experts and their new Series PFM Digital Flow Switch using MEMS technology, this simply isn't the case.Developed initially to detect microchip component adsorption in vacuum and early clogging in both filter and nozzle applications, the new Series PFM Flow Switch is incredibly compact and lightweight compared to existing flow sensors thanks to its micro electro mechanical system (MEMS) sensor. With its unique integrated flow adjustment valve, which can be added or disconnected by simply removing its retaining clip, linear flow rate can be adjusted manually by rotating the flow rate adjustment knob. Further features of the PFM are the dual colour digital display which indicates any performance irregularities at a glance and due to its MEMS sensor both straight or elbow piping options are possible making this the perfect flow switch when space limitations are an issue.Currently the PFM range is available in four maximum flow rate options 10, 25, 50 and 100 l/min and is suitable for use with air, nitrogen, argon or carbon dioxide.

For applications requiring extremely accurate small work piece detection, such as in the electronics industry, the use of a standard pressure sensor may not be sufficiently precise enough to match these exacting and very specific needs. However, thanks to the R&D engineers at SMC, the world leaders in pneumatic technology and their latest flow sensor – Series PFMV – these concerns may now be a thing of the past.Developed initially for the semiconductor market, the PFMV Flow Sensor which uses very low pressure suction, through its specially designed flow passage, can detect the presence of a work piece during an application by simply checking for any flow rate changes. With a response speed of 5ms or less, this suction technology can also be successfully used to detect blockages in applications using nozzles or leakage in moulding applications which often result in minute pin holes and ultimate component rejection.Further features of the RoHS compliant PFMV are its extremely compact size making it ideal for when space is an issue, its facility to be mounted together – similar to a manifold arrangement –, its low flow rate, and its abilities to determine a vacuum break and to be used with either a digital or analogue display including auto-shift input.