Low Cost Data Acquisition

GW Instruments are a manufacturer of data acquisition hardware and software, recently  announced a new card cage based data logger for measurement and control; along with a suite of low-cost, high-accuracy plug-in modules.

Low Cost Data Acquisition

Introducing our range of PC based low cost data acquisition by GW Instruments!

Our low cost data acquisition option is a new product family is called “instruNet i4xx” and consists of four different card cages (4, 8, 12, 16 slots), five different plug-in cards, and three different wiring boxes.

FEATURESRight Click DOWNLOAD PHOTOS to see picture

  • Analog and digital I/O cards enable one to create an 8 to 256 channel measurement system.
  • Cards easily plug into a 4, 8, 12 or 16 slot card cage that communicates with Windows computer via USB 2.0.
  • Connect directly to Voltage, Current, Resistance, Thermocouple, Thermistor, Strain Gage, Load Cell, RTD, and Accelerometer sensors.
  • Free instruNet World strip chart recorder software supports Windows XP, Vista, 7 and 8 (32-bit or 64-bit).
  • i51x wiring boxes easily attach to i4xx series cards.
  • Compatible with LabVIEW, DASYLab, C and Visual BASIC Software.
  • Digitize any combination of channels at 166,000 samples per second aggregate.
  • Optional anti-aliasing filter.
  • Reduce noise by placing i4xx cards near sensors and up to 100 meters from noisy computer.
  • Low Cost Data Aquisition

InstrunetAbout the Instrunet i4


Why Choose the Instrunet i4?

instuNet is better than other systems for the following reasons:

  • instruNet is the highest-accuracy data acquisition system for performing low-level measurements (e.g. ±100mV), as explained here. The instruNet card cage does not contain a noisy processor, which makes it easier to do accurate low level measurements. Low level measurements are required by many sensors, such as thermocouples, strain gages and load cells; which respectively measure temperature, bending and weight.
  • instruNet is the lowest-cost data acquisition system with UNIVERSAL inputs, as explained here. Universal inputs support the direct connection to common sensors, sometimes with the help of one additional shunt resistor. instruNet does this at $124 per-channel with an 8-channel system, with unprecedented accuracy.
  • instruNet is the lowest-cost CARD CAGE data acquisition system, as explained here. Card cages enable one to mix and match modules as needed.
  • instruNet is the lowest-cost data acquisition system with optional anti-aliasing filters. Anti-aliasing filters eliminate errors caused by high frequencies that enter the digitizer, as explained here.
Acquisition Card Options


Communications card connects an iNet-400 card cage to a Windows computer via an instruNET iNET-240 USB controller


Provides 20 single-ended (SE)/10 differential (DI) voltage input channels and 4 universal digital I/O


Provides 6 differential (DI) voltage input channels; each of which has its own amplifier and low pass filter


Provides 16/8 DI/SE voltage input channels with a 16-bit A/D converter, 4 voltage outputs, and 4 digital I/O


Provides 12 universal digital I/O (20 mA sink, -10 to 30 V) and 16 digital I/O (200 mA sink, -10 to 30 V)

Optional Anti-Aliasing Filter
low_pass_filter_simple_189w_152hThe optional 8-Pole i500 analog low pass filter daughterboard is ideal for anti-aliasing. For a summary of aliasing and why you might need an AFS filter, click here. The i500 provides extremely low ±0.01 dB maximum passband ripple for Fin/Fc ≤ 0.5. If one uses further oversampling, digital filtering and desampling; then passband ripple is ±0.002 dB for Fin/Fc ≤ 0.8 due to the accuracy of a 30-pole digital filter. The end user installs between 1 and 6 filter daughterboards onto each i423 card, one per channel.  
instruNet Software
instruNet includes software to interrogate, test, configure, and do I/O with all network channels. This includes an application program called “instruNet World” and interfaces to Visual Basic, C, and C . instruNet software can configure all I/O channels, store your settings, view digitized data in real time, stream data to disk, and scroll through your waveform post-acquisition. instruNet software runs on Windows computers.

Instrunet World 
Dasy Lab 
Instrunet World
Visual Basic 
Istrunet Scope 
Direct to Excel
Visual Basic
Instrunet Scope
Connect Directly To Sensors
The table below shows which sensors directly connect to each hardware product. The numbers in the table refer to number of channels; and if you click on those numbers, you will be redirected to the measurement accuracy for that sensor and product. The following sensors require an external shunt resistor: RTD, thermistor, resistance measurement, current measurement, ¼ bridge strain gage, and ½ bridge strain gage. Thermocouple sensors require an i51x Wiring Box attached to the i4xx card 28. In order to do voltage measurement, one needs at least one i430 A/D card. One only needs one i43x a/d card per card cage.
i555 Starter System
The i555 Starter System, shown to the right, provides the following: Usb 2.0 High Speed Data Acquisition Hardware for Windows ≥ Xp Sp2, Vista or 7 (Xp/Vs/7/8) instruNet Software 16se/8di Voltage Inputs with 16-bit A/D Converter 2x Precision Voltage Outputs (±10V, 14bit D/A) 2x Voltage Outputs (0.. 10V, 8bit D/A) 4x Universal Digital I/O (20mA sink, -10V..30V) Connect Directly To Sensors: Voltage, Thermocouple, Thermistor, RTD, Load Cell, Strain Gage, Potentiometer, Current, Resistance Easily expand via 2 free slots in 4 slot i4xx Card Cage The i555 includes the following products: i240, i430, i510, i400, i410, i312.  
i555 Starter system
Maximum Sample Rates
The following table shows maximum aggregate sample rates for an i240 USB controller attached to an i4xx Card Cage. To calculate the sample rate for each channel, divide by the number of channels attached to the i240 controller. For example, if the maximum aggregate sample rate is 166Ksamples/sec/controller, and you digitize 4 channels, then you could digitize each channel at 41Ks/sec/channel. For more details on this table, click here. One can attach up to four i240 controllers to a computer to increase total system throughput.
i51x Wiring Boxes
#iNet-510 #iNet-511 #iNet-512 i51x wiring boxes easily bolt to i4xx cards. The i510 is the simplest and is included with the i555 starter system. The i511 includes 8 bnc connectors. The i512 has a vRef/2 source that is used to help complete 1/4 bridge and 1/2 bridge strain gage circuits. If you are measuring thermocouples, then the i510 is the only wiring box that will work, since it contains an internal temperature sensor that measures the temperature of the i510 screw terminals. For more details on each, click on the model number in the below table.
Theory Of Operation
instruNet is a low-cost hardware card cage that attaches to Windows computers via USB 2.0. The advantage of a card cage is one can mix and match modules as needed, to build exactly what they need. The advantage of the instruNet card cage is cost. For example, instruNet 4 to 16 slot chassis, whereas comparable chassis are 2x to 4x more costly. The instruNet card cage typically has one A/D measurement module; additional modules provide signal conditioning. The conditioned analog signal is routed to the A/D module via the backplane. This is dramatically different from comparable systems, which place A/D measurement electronics on each module. The advantage of the instruNet topology is cost. After the first module is installed, additional instruNet channels are conditioned at approximately $40 per channel, whereas comparable systems typically cost 2x to 8x more. instruNet measurement modules have universal inputs that enable one to directly connect each channel to one of: Thermocouple, Thermistor, Strain Gage, Load Cell, Counter/Timer, RTD, Voltage, Current, Resistance and Accelerometer. Absolute accuracy for all of these sensor types is specified. In some cases, the end user adds an external shunt resistor. The advantage of universal inputs is cost. The optional 8-pole i500 analog low-pass filter daughterboard provides very accurate anti-aliased data at low cost.
Connect to Computer Via USB
Each instruNet Network is controlled by an instruNet i240 DSP controller card that attaches to a Microsoft 32bit or 64bit Windows ≥ Xp Sp2, Vista, 7 or 8 computer via High Speed USB 2.0 at 480mbit/sec. Each i240 Controller is an independent computer in itself that utilizes a powerful 32-bit DSP processor and onboard RAM to control all aspects of data acquisition along its network. All real-time tasks are off-loaded to this processor, therefore the host computer is not burdened with real-time issues. Each instruNet network supports up to 4 instruNet iNET-400 card cages.i2x0_4slot_i410_i430_dwg







No Information Available.

No Information Available.