The internal impedance is high and the output electrical signal is very weak. The main function of the preamplifier is to convert the high impedance output of the piezoelectric sensor into a low impedance output, and also to amplify weak signals.
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Pressure Transmitter Water Oil Fuel Gas Air M20*1.5 DC24V 4-20mA 0-10V RS485 Optional Stainless Steel Pressure Transducer Sensor
Aliexpress UK
±2% FS small output error including nonlinearity, hysteresis and repeatability over temperature. Thread: 1/8" NPT. Thread: 1/8"-27 NPT. Thread: 1/8"-27 NPT. Wiring: red is +5V; black is ground; green is signal output.
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water oil fuel gas air pressure transmitter G1/4 12-36V 4-20mA 0-600bar optional stainless steel pressure transducer sensor
Aliexpress UK
water oil fuel gas air pressure transmitter G1/4 12-36V 4-20mA 0-600bar optional stainless steel pressure transducer sensor
Aliexpress UK
40mm Display Stainless Steel 1/8" NPT Thread Filter Hydraulic Pressure Gauge Meter Manometer, for Water Pressure Testing Dropsh
Aliexpress UK
pressure sensor transducer transmitter for water oil fuel gas air 1/8NPT DC 5V ceramic sensor stainless steel 5-300psi optional
Aliexpress UK
pressure sensor transducer transmitter for water oil fuel gas air 1/8NPT DC 5V ceramic sensor stainless steel 5-300psi optional
Aliexpress UK
pressure sensor transducer transmitter for water oil fuel gas air 1/4NPT 5-12V ceramic sensor stainless steel 5-300psi optional
Aliexpress UK
Pressure Sensor Transmitter For Water Oil Fuel Gas Air G1/4 5V Ceramic Sensor Stainless Steel 0.5Mpa 1.2Mpa Transducer
Aliexpress UK