The Setra 225 is an ultra-high purity pressure transducer built for gas delivery systems in semiconductor process and control applications, where cleanliness, stability, and high throughput all matter. It has a rotatable housing so zero and span can be fine-tuned in the field with a 12-turn potentiometer, and the standard interface is a rotary male/internal end face seal, with other pressure interface options available.
Inside, it uses Setra’s variable capacitance technology, with VIM/VAR 316L stainless steel diaphragms and insulated electrode plates: as gas pressure rises, the diaphragm flexes slightly and changes the capacitance the electronics read as a proportional signal. Output is 5VDC, 10VDC, adjustable ratiometric, or 4-20mA, wired through a 6-foot multi-core cable with bayonet, D-sub, or M12x1 connector options. Wetted surfaces are electropolished to 7 Ra maximum, and every sensor is mass spectrometer helium leak tested to 1×10-9 ATM.CC/sec, with an internal cavity volume of only 0.11 in³ so it purges quickly. Manufacturing runs through rinsing, high purity hot nitrogen purging, drying, double-layer packaging, nitrogen filling and sealing before shipment, and every unit is calibrated to ANSI-Z540 with NIST traceability.
From our experience, this is specified wherever the process gas itself cannot tolerate contamination, and a fast-purging, low-leak instrument is worth paying for. Before we quote this, we would normally check the pressure range, connector type, and mounting/interface style needed. Hope this helps.
