Products for USB Sensing and Control

Products for USB Sensing and Control

PHIDGETS Inc.

Unit 1 - 6115 4 St SE
Calgary AB  T2H 2H9
Canada
+1 403 282-7335

Wheatstone Bridge Phidget

ID: DAQ1500_0

Measure up to 2 load cells or Wheatstone Bridge-based sensors with this input module. Connects to a VINT port.

$30.00

Quantity Available: 386

Qty Price
5 $28.50
10 $27.00
25 $24.00
50 $21.00
100 $19.50
250 $18.00
500 $16.50
1000 $15.00

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. See the "Compatible Products" tab for a list of VINT Hubs.



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

Board
Controlled By VINT
Number of Bridge Inputs 2
Bridge Inputs
Bridge Voltage Resolution 59.6 nV/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
Electrical Properties
Current Consumption Min 25 μA
Current Consumption Max *bridge current plus 1.5 mA
Physical Properties
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.

Software Objects

Channel NameAPIChannel
Bridge Input VoltageRatioInput 0 - 1

API


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Documents

Library & Driver Downloads

Code Samples

APILanguageOS
VoltageRatioInput C Multiple Download
VoltageRatioInput C# Windows Download
VoltageRatioInput Java Multiple Download
VoltageRatioInput JavaScript Any Download
VoltageRatioInput Objective-C macOS Download
VoltageRatioInput Python Multiple Download
VoltageRatioInput Visual Basic .NET Windows Download

Projects

Product History

Date Board Revision Device Version Comment
June 20170104Product Release

Getting Started

Welcome to the DAQ1500 user guide! In order to get started, make sure you have the following hardware on hand:


Next, you will need to connect the pieces:

DAQ1500 Functional.jpeg
  1. Connect the DAQ1500 to the VINT Hub using the Phidget cable.
  2. Connect a load cell or strain gauge to the DAQ1500. See your product's data sheet for connection details.
  3. Connect the VINT Hub to your computer with a USB cable.


Now that you have everything together, let's start using the DAQ1500!

Using the DAQ1500

Phidget Control Panel

In order to demonstrate the functionality of the DAQ1500, the Phidget Control Panel running on a Windows machine will be used.


The Phidget Control Panel is available for use on both macOS and Windows machines. If you would like to follow along, first take a look at the getting started guide for your operating system:


Linux users can follow the getting started with Linux guide and continue reading here for more information about the DAQ1500.

First Look

After plugging the DAQ1500 into your computer and opening the Phidget Control Panel, you will see something like this:

DAQ1500 Panel.jpg


The Phidget Control Panel will list all connected Phidgets and associated objects, as well as the following information:

  • Serial number: allows you to differentiate between similar Phidgets.
  • Channel: allows you to differentiate between similar objects on a Phidget.
  • Version number: corresponds to the firmware version your Phidget is running. If your Phidget is listed in red, your firmware is out of date. Update the firmware by double-clicking the entry.


The Phidget Control Panel can also be used to test your device. Double-clicking on an object will open an example.

Bridge Input

Double-click on the Voltage Ratio object, labelled Bridge Input, in order to run the example:

DAQ1500 VoltageRatioBridge Example.jpg


General information about the selected object will be displayed at the top of the window. You can also experiment with the following functionality:

  • Modify the change trigger and/or data interval value by dragging the sliders. For more information on these settings, see the data interval/change trigger page.
  • Toggle the Enable checkbox in order enable/disable the DAQ1500.
  • Select a gain from the Bridge Gain drop-down menu. For more information about choosing the best gain, see the technical section.


Technical Details

Gain-sensitive Specifications

Gain Resolution (nV/V) Noise Floor (nV/V) Output Range (mV/V)
1x 59.60 5000 ±500
2x 29.80 2600 ±250
64x 0.931 133 ±78.125
128x 0.466 87 ±39.063

Connecting your Strain Gauge/Load Cell

Load cells are pressure sensors that can be used with the DAQ1500. For more information, see our Load Cell Primer.


If no documentation is available for your strain gauge, it’s possible to use a multimeter to determine how to connect it, provided there are no electronics in the sensor. First, measure resistance between the 4 wires. There are 6 combinations - two combinations will have a resistance 20-40% higher than the other four. Choose one of these high-resistance combinations, and wire it into 5V and G on the DAQ1500. Connect the other two wires into +/-. Apply a load, if the V/V responds in the opposite way to your expectations, flip the +/- wires.

Measurement Considerations

The DAQ1500 is designed to measure voltages as a ratio of the supply voltage - it’s not practical to make measurements of absolute voltages with this product.


For maximum accuracy, all wires from the DAQ1500 to the sensor should be the same length and thickness. Changes in temperature will change the resistance of the wires - if they are all the same, the errors will cancel out.


The bridge inputs can be powered down, reducing power consumption with DAQ1500 sensors, and useful for reducing heating of sensors, which can introduce errors.

Current Consumption

The amount of current consumed by the DAQ1500 varies based on the data interval you select:

DAQ1500-current.jpg


Use the following equation to approximate the relationship between current consumption and data interval (up to a maximum data interval of 60000ms):



This figure is the no-load current, so to estimate total current consumption, you'll need to measure the current consumption at a known data interval so you can determine the offset, which should be no higher than 50mA.

What to do Next

  • Software Overview - Find your preferred programming language here to learn how to write your own code with Phidgets!
  • General Phidget Programming - Read this general guide to the various aspects of programming with Phidgets. Learn how to log data into a spreadsheet, use Phidgets over the network, and much more.
  • Phidget22 API - The API is a universal library of all functions and definitions for programming with Phidgets. Just select your language and device and it'll give you a complete list of all properties, methods, events, and enumerations that are at your disposal.

VINT Hubs

This Phidget is a smart device that must be controlled by a VINT Hub. For more information about VINT, have a look at the VINT Primer. You can use a Phidget Cable to simply and easily connect the two devices. Here's a list of all of the different VINT Hubs currently available:

Product Board
Image Part Number Price Number of VINT Ports
HUB0000_0 $30.00 6
SBC3003_0 $120.00 6

Load Cells

You can connect up to four load cells to the DAQ1500 in order to measure the amount of strain in the cell. See the product page or manual for your load cell to learn how to hook it up. We have a variety of types available to measure different types of strain: shear, compression, and tension. See the Load Cell Primer for more information.

Product Sensor Properties
Image Part Number Price Sensor Type Weight Capacity Max Creep Zero Balance Cell Repeatability Error Max Cell Non-Linearity Max Cell Hysteresis Max
3132_0 $6.00 Shear Load Cell 780 g 1.6 g/hr ± 11.7 g ± 390 mg 390 mg 390 mg
3133_0 $7.00 Shear Load Cell 5 kg 5 g/hr ± 75 g ± 2.5 g 2.5 g 2.5 g
3134_0 $7.00 Shear Load Cell 20 kg 20 g/hr ± 300 g ± 10 g 10 g 10 g
3135_0 $7.00 Shear Load Cell 50 kg 50 g/hr ± 750 g ± 25 g 25 g 25 g
3136_0 $45.00 Compression Load Cell 50 kg 20 g/hr ± 500 g ± 100 g 100 g
3137_0 $45.00 Compression Load Cell 200 kg * 40 g/hr * ± 2 kg * ± 200 g * 400 g
3138_0 $45.00 Compression/Tension Load Cell 100 kg
3139_0 $7.00 Shear Load Cell 100 g ± 50 mg 50 mg 50 mg
3140_0 $50.00 Compression/Tension Load Cell 500 kg
3141_0 $50.00 Compression Load Cell 1 Mg

Strain Gauges

Strain gauges are ideal for situations where you want to monitor the strain in a material that's already a part of your project. By attaching strain gauges in a strategic way, you can effectively turn a load-bearing member into a custom load cell. You can read strain gauges using the DAQ1500 by connecting them as described in the Strain Gauge Primer.

Product Sensor Properties Electrical Properties
Image Part Number Price Sensor Type Strain Gauge Mount Type Resistance Value
3142_0 $12.50 Torque Half-bridge Strain Gauge Steel (per quarter-bridge) 1 kΩ
3143_0 $12.50 Torque Half-bridge Strain Gauge Aluminum (per quarter-bridge) 1 kΩ
3144_0 $15.00 Half-bridge Strain Gauge Steel (per quarter-bridge) 1 kΩ
3145_0 $15.00 Half-bridge Strain Gauge Aluminum (per quarter-bridge) 1 kΩ
3146_0 $17.50 Full-bridge Strain Gauge Steel (per quarter-bridge) 1 kΩ
3147_0 $17.50 Full-bridge Strain Gauge Aluminum (per quarter-bridge) 1 kΩ

Phidget Cables

Use a Phidget cable to connect this device to the hub. You can solder multiple cables together in order to make even longer Phidget cables, but you should be aware of the effects of having long wires in your system.

Product Physical Properties
Image Part Number Price Cable Length
3002_0 $2.00 600 mm
3003_0 $1.50 100 mm
3004_0 $3.00 3.5 m
3034_0 $1.50 150 mm
3038_0 $2.25 1.2 m
3039_0 $2.75 1.8 m

Here are our Bridge Interfaces:

Product Board
Image Part Number Price Controlled By Number of Bridge Inputs
1046_0 $90.00 USB 4
DAQ1500_0 $30.00 VINT 2