8400, Scanner Digitizer Interface

The Scanner Digitizer Interface (SDI) configuration of the System 8400 represents a major advancement in electronic pressure scanning for windtunnel applications. This configuration executes digital temperature compensation on a new generation of ESP pressure scanners to significantly improve overall accuracy while reducing the frequency of on-line calibrations and the time to perform them. The technology dramatically enhances data quality while equally increasing productivity.

The compact scanner interface (SDI) is located close to the scanners to locally digitize analog signals and transmit the resultant data via fiber optic cable to a Fiber Interface Unit (FIU) within the 8400 System Processor. The FIU-SDI combination replaces the previous combination of a Scanner Digitizer Unit (SDU) and its remote interface (IFC) while providing increased functionality and data quality. Longer, yet significantly smaller cabling is now possible between the 8400 System Processor and the ESP scanners. Data quality is greatly enhanced since all data acquisition is local to the scanners and only digital data traverses the fiber optic link between the SDI and FIU.

The new DTC Series of ESP scanners incorporates Digital Temperature Compensation (DTC) technology, which individually monitors the temperature of the sensors and compensates for any changes using pressure and temperature algorithms stored in an onboard EEPROM. The embedded memory also houses scanner identity and date of last calibration. When used with the SDI configuration, the scanner supports programmable gain manipulation to derange its full-scale pressure range by 66%. New diagnostic features include calibration valve position indication and excitation voltage sense to significantly decrease setup time.

Existing conventional 8400 systems can be upgraded to the SDI configuration with the addition of the new hardware and a firmware upgrade. Both conventional and DTC ESP scanners are supported by this new configuration.