Bridge-based sensors are are a common type of resistive sensor that produce a very small voltage drop. Load cells, strain gauges, pressure sensors, and piezoelectric sensors are all examples of sensors that usually operate in this way. In order to measure these tiny voltage changes, you need a Wheatstone bridge input. The Wheatstone Bridge Phidget uses a high-resolution ADC to to read up to two of these signals and plugs into any VINT port.
Accurate and Adjustable
This board is equipped with a 24-bit analog to digital converter, resulting in accurate measurements at resolutions as high as 59.6 µV/V. The bridge gain can be changed in software to 1, 2, 64, or 128, allowing you to get the best resolution for the range of the sensor you use. An error event will be launched whenever the measurement value saturates, so your program can dynamically change the gain when necessary.
Product Specifications for DAQ1500_0 Wheatstone Bridge Phidget
|Number of Bridge Inputs||2|
|Bridge Voltage Resolution||59.6 μV/V|
|Sampling Interval Max||60 s/sample|
|Sampling Interval Min||20 ms/sample|
|Bridge Current Max||50 mA|
|Input Voltage Limit Min||Ground + 0.25V DC|
|Input Voltage Limit Max||5V Supply – 0.25V DC|
|Current Consumption Min||25 μA|
|Current Consumption Max||*bridge current plus 1.5 mA|
|Recommended Wire Size||16 – 26 AWG|
|Operating Temperature Min||-40 °C|
|Operating Temperature Max||85 °C|
* – The extra 1.5mA of current consumption varies depending on the data interval selected. See the technical section of the User Guide for details. Additional gain-sensitive specifications can also be found there.