Pacific’s Ruggedized Model 7300 increases the bandwidth and sample rates of the popular 7200 ruggedized data systems. A network appliance, each module conditions, amplifies and digitizes the outputs of up to sixteen strain gage, bridge or voltage transducers. The rugged enclosure is designed for installation in wind tunnels, engine test stands and other facilities where it is desired to locate the DAS close to the test article, ultimately reducing installation and cable costs as well as improving signal quality and reliability.
Fully self-contained, the 7300 provides transducer excitation, bridge completion and balance. The transducer output is amplified, filtered to remove signal components that could produce alias errors and digitized to 24-bit resolution. The digitized transducer output is digitally processed providing multiple sample rates, an 80 dB/octave FIR filter and 32-bit floating point output format in millivolts referred to input, millivolts referred to output or user defined engineering units.
Four models are available that differ in their excitation and signal conditioning capabilities. Model 7316 for strain gage and bridge transducers has programmable voltage excitation, bridge completion for 120 and 350 Ohm strain gages, shunt calibration and automatic balance. Model 7324 is similar to 7316 but it also includes an option to AC couple the input. Model 7320 is similar but provides regulated power for transducers with internal electronics. Model 7318 is for voltage inputs. The amplified transducer signals are digitized, processed and output at up to 100k samples per second, as selected for individual channels. A digital signal processor (DSP) provides low-pass filtering selectable from 10 Hz to 50 kHz with 80 db/octave roll-off.
Each module has a 1 Gigabit Ethernet interface for control and data output, which simplifies system wiring and provides remote and distributed operation. IRIG time may be employed to synchronize sampling on multiple modules within 10 microseconds, or a TTL timing signal may be used to achieve better than 1 microsecond time alignment. Multiple modules with up to 4,096 channels may be connected on a single Ethernet LAN.
The module enclosure features interchangeable end plates that provide fully sealed, ambient air or forced air cooling. Forced air cooling provides the capability to operate over a wide temperature range according to application requirements. Occupying less than 500 cubic inches and weighing less than 14 pounds, the 7300 system can be installed in locations previously not suitable for data acquisition systems. The Ethernet interface and IRIG timing make it easy to distribute modules throughout the test facility, minimizing sensor cabling and installation costs.
The 7300 does not sacrifice performance for size or portability; it features higher accuracy than most systems designed for a laboratory environment. Accuracy is better than 0.05% for gains up to 200 and 0.1% for gains above 200 over the temperature range -20°C to +50°C, which can be extended to higher temperatures by forced air cooling.
Model 7300 is supported by Pacific’s PI770 software that provides a ready-to-run application and an SDK for user program development. Calibration and performance verification is accomplished by PANEL72 Maintenance and Calibration software. The ACS2000 Automatic Calibration System automates performance verification and periodic instrument calibration.
7314: Six-wire input, signal input (2), excitation (2), excitation sense (2) and shield. Programmable bridge completion for half bridges and 120 Ohm and 350 Ohm quarter bridges.
7316: Six-wire input, signal input (2), excitation (2), excitation sense (2) and shield. Programmable bridge completion for half bridges and 120 Ohm and 350 Ohm quarter bridges.
7318: Two-wire input, signal input (2) and shield.
7320: Four-wire input, signal input (2), transducer power (2) and shield.
7324: Six-wire input, signal input (2), excitation (2), excitation sense (2) and shield. Programmable bridge completion for half bridges and 120 Ohm and 350 Ohm quarter bridges. Programmable AC or DC coupled input.
7314 & 7316: Automatic by program control. Balance accuracy ±0.025% of range, ±1 mV RTO. Range set by resistor up to 25 mV/V, 2.5 mV/V (350 Ohms) installed.
7316: Constant voltage with remote sensing. Programmable from 1 to 15 Volts with 1 mV resolution. Calibrated 1-Volt steps ±0.1%. 50 mA limited to 70 mA maximum.
90 dB at 10 kHz
The system maintains ±0.05% (Model 7316 ±0.025%) full scale (2-sigma) uncertainty for gains up to 200 and ±0.1% full scale (2-sigma) uncertainty for gains above 200 over the operating temperature range.
The output of a temperature stable, 5-Volt internal reference with ±0.01% stability, X1.0, X0.1 and X0.01 ±0.05% attenuator and 0.0015% resolution on each attenuator setting may be applied to each channel. Accuracy is ±0.2% for gains to and including 100 and ±0.3% for gains over 100. Stability is ±0.01%. Output of the internal reference can be measured on an external connector.
MIL, 1/4-turn locking
7314 - 16-Ch Strain/Bridge Data Acquisition (AC / DC coupled)
7316 - 16-Ch Strain/Bridge Data Acquisition (DC coupled)
7318 - 16-Ch Voltage Data Acquisition (DC coupled)
7320 - 16-Ch Transducer Data Acquisition (DC coupled)
7324 - 16-Ch Strain/Bridge/IEPE Data Acquisition (AC / DC coupled)