Large Channel Counts
When input/output channel counts reach the hundreds or thousands, special requirements are placed on data acquisition systems. First, the hardware must be modular and inexpensively expandable. Second, the onboard processing requirements must increase and network performance must be optimized as channels are added. Third, a convenient method is needed for configuring and displaying large numbers of channels.
NetAcquire systems offer a bus-based input/output architecture. Plug-in interface cards offer convenient expansion in multiples of 2, 8, or 16 channels. The onboard software inside each NetAcquire system takes care of all the details of controlling additional channels and managing expansion control signals.
Onboard Processing and Network Optimization
Even relatively slow data rates add increased processing requirements as channel counts become large. These systems benefit from integrated high-performance processors (see high throughput data processing).
Network bandwidth requirements also increase. NetAcquire Publish/Subscribe can be used to optimize network bandwidth by only transmitting channels that were explicitly requested by each network user. In addition, real-time data compression avoids sending redundant information about channels that are changing slowly.
Configuration and Display
NetAcquire graphical configuration screens automatically reflect the number of input/output interface cards installed in a system. Large channel configurations need only be entered once, since configuration settings are stored in nonvolatile memory for future use. Integration with externally-maintained databases of test and measurement parameters is also available using customized data exchange applications.
NetAcquire data displays are designed to avoid arbitrary limits on the number of channels. In addition, screens can be customized to display different subsets of active input channels in order to present the most relevant data on each machine.