Setra’s Model 217 designed for panels and modular “Block” gas sticks. Setra 217 is ideal for pressure measurement applications that require exceptional insensitivity to environmental extremes, example the temperature transients resulting from the flow of cold gas.
The Model 217, available with a C-Seal or W-seal down-mount pressure port, the small swept sensor chamber for easy to purge. 316L VIM/VAR stainless steel is the standard material for all wetted parts. Passivated to 5 Ra (7 Ra. max.) finish, which eliminates surface irregularities and provides the proper surface chemistry for corrosion resistance, assuring contaminant-free gas distribution. Every sensor is mass spectrometer helium leak tested to 1 x 10-9 atm.cc/sec.
The top external zero and span adjustments complete this unique design for all UHP down-mount applications. Setra’s patented variable capacitance sensor features a 316L stainless steel diaphragm and an insulated electrode plate. A variable capacitor formed between the electrode plate and the sensor body. The increase in pressure makes a slight rounding of the diaphragm, while reduces the capacitance. The capacitance change is detected and converted to a highly accurate linear DC electric signal by Setra’s unique custom integrated circuit, utilizing a patented charge balance principle. The entire Ultra-High Purity series of Setra based on Setra’s proven capacitive sensing technology with highly precise and stable voltage or current output signals hence virtually EMI/RFI immune.