Inline Strain Gauge Signal Conditioning Amplifier/Transmitter

FUTEK's ICA105 4-20ma load cell transmitter (aka load cell amplifier 4 20ma) is an Inline Strain Gauge Signal Conditioning Amplifier and Transmitter with Current Analog Output of 0-20 mA , 4-20 mA , 10 +/-10 mA , or 12 +/-8 mA . It features 1 KHZ Bandwidth , Male DB9 Connector. 

The function of a load cell amplifier circuit is to capture the signal from the load cell or torque sensor and convert it into a higher level of an electrical signal. In order to do so, the mV/V low amplitude output of the load cell goes thru four different signal conditioning steps:

1) Excitation Voltage: Full-bridge load cells or torque sensors require an excitation voltage from the Wheatstone bridge amplifier to feed the strain gage Wheatstone bridge and generate their output signal as a ratio of the input excitation voltage.

2) Filtering: Analog sensor signals are susceptible to electrical noise and/or residual ripple voltage, which can distort or skew measurements. Noise needs to be filtered out before you can capture an accurate signal. 

3) Amplification: A full-bridge strain gage sensor can output a signal in the nanovolt through millivolt range. When your DAQ or PLC is limited to measuring volts, you will need an strain gage amplifier to convert millivolts to a larger signal.

4) Signal conversion: The majority full-bridge load cells and force measurement sensors or transducers generate an analog output in the millivolt range (mV/V). Thus, signal processing is traditionally analog. So, if you req PLC or DAQ system requires an amplified analog (i.e.: 4-20 mA, 0-10 VDC) or a digital output (USB, SPI), the load cell or torque sensor needs a strain gage signal conditioner to convert the mV/V signal to the required signal output.