GW Instruments - InstruNet
instruNet
instruNet is a family of data acquisition hardware that provides ten's of microVolts of absolute accuracy instead of ten's of milliVolts, at the same cost, and at the same throughput rates as the typical general purpose data acquisition board. It does this with a completely different topology where the analog electronics are put close to the sensor in electrically quiet boxes outside of the computer, and the noisy digital electronics are left inside the computer.
The external boxes, shown above, contain signal conditioning amplifiers for each channel, and can therefore directly attach to sensors such as thermocouples, RTD's, strain gages, resistance sources, current sources, and voltage sources; and return engineering units (e.g. "Volts","Amps"). For a larger picture, click here.
At the heart of the system is a PCMCIA or PCI bus controller board, shown to the right, that plugs into a Windows 95/98/Me/NT/2K/XP or Macintosh computer (except the PCMCIA card on Win NT). For compatibility details, click here. For a larger picture, click here. The controllers contain a 32bit microprocessor with 256KB of RAM that manages the external network of devices. All real-time tasks are off-loaded to this processor, therefore the host computer is not burdened with real-time issues. The instruNet 100 Network Device, pictured at thetop of this page (the long black box with BNC connectors), provides:
- 16se/8di 14bit analog inputs with +/-5V, +/-.6V, +/-.08V & +/-.01Vrange
- 8 Channels +/-5V 8bit analog outputs
- 8 digital I/O bits
The instruNet 100 includes 44 screw terminals, or optionally 16 BNC's for analog inputs. The controller's themselves provide 10 counter/timer channels that each can function as a digital input bit, a digital output bit, a clockoutput channel, or a period measurement input channel.
i100 Network Devices
Network Devices typically provide voltage input channels, voltage output channels, digital inputs and digital outputs; as noted below.
| Model | Voltage Inputs | Voltage Outputs | Digital I/O | ||||
| # of Channels | Input Range | Absolute Accuracy | # of Channels | Write Accuracy | Read-back Acc-uracy | ||
| 100 | 16ch w/screw terminal access | ±5V ±.6V ±80mV ±8mV |
±1500µV ±150µV ±45µV ±30µV |
8ch with 4mA/ 1KpF Drive Capability | ±40 mV | ±3 mV | 8 bidir-ectional I/O Bits |
| 100B | Same as #iNet-100, yet with 16 additional BNC connectors for 16se voltage inputs. | ||||||
| 100HC | Same as #iNet-100, yet with voltage outputs that have 15mA/.01uF drive capability. | ||||||
i2x0 Controllers
Each instruNet Network is controlled by a Network Controller board that installs into a computer. A different controller board is used with each common bus interface (e.g. PCI, PC-Card), yet they are all very similar internally. Each Controller is an independent computer in itself that utilizes a powerful 32-bit microprocessor and onboard RAM to control all aspects of data acquisition along its network. One can install as many Controllers as desired, space permitting, since each controller operates independently. Each network supports up to 8 Network Devices. Each Device is a small box (e.g. 10cm x 12cm x 25cm) that is connected in a daisy-chain configuration to form a chain of Devices. Each network can be up to 300 meters long. All networks are anchored with an instruNet Terminator at the far end, and an instruNet Controller at the near end. This makes instruNet a cost effective method for designing large scale, high speed, multi-channel data acquisition systems. The following table summarizes the instruNet Controllers.
| Mode | Controller | Bus | Size | Computer Required |
| 200 | PCI Controller | PCI> | 7" x 4" | Windows 95/98/Me/Nt/2k/Xp/Vs Computer with PCI Rev ≥2.0 compliant, 32-bit, +5V slot; or Macintosh OS >= 8 (must boot OS 9 if on OS >= 10.2 Mac) with PCI Slot. |
| 230 | PC-Card Controller | PC-Card | 2" x 3" | Windows 95/98/Me/2k/Xp/Vs (not NT) Computer or Macintosh OS >= 8 (must boot OS 9 if on OS >= 10.2 Mac) PPC/G3/G4/> Powerbook computer (i.e. Models 1400, 2400, 3400, 5300, >=G3). Requires Type II PCMCIA compliant ≥ v2.1 (or ≥ PC-Card 95) PC-Card slot. |
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"; drivers; interfaces to C, and Visual BASIC. instruNet World and the instruNet Driver 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 both a PC and a Macintosh OS >= 8 (must boot OS 9 if on OS >= 10.2 Mac, for details click here).
Free Updates
Free software and manual updates are available here.
The following table summarizes the computer required to run instruNet. For more details, click here.
| Model | Controller | Computer Required | OS Required | RAM Required | HD Required | Slot Required |
| 200 | PCI Controller | IBM PC or Compatible ≥ 80486 | Windows 95/98/Me/ Nt/2k/Xp/Vs | ≥ 4MB | ≥ 6MB free |
PCI Slot, ≥6.8", Rev ≥2.0 compliant, 32-bit, +5V
|
| 230 | PC-Card Controller | IBM PC or Compatible ≥ 80486 | Windows 95/98/Me/ 2k/Xp/Vs (not NT) | ≥ 4MB | ≥ 6MB free |
Type II PC-Card Slot with ≥ v2.1 PCMCIA compliant card services
|
| 230 | PC-Card Controller | Macintosh PPC/G3/ G4/> Powerbook1 | OS >= 8 (must boot OS 9 if on OS >= 10.2 Mac)1 | ≥ 4MB | ≥ 6MB free |
Type II PC-Card Slot with ≥ v2.1 PCMCIA compliant card services
|
1For more details on Macintosh compatibility, please click here.