8-Channel Isolated 4-20 mA current sinking D/A Board with Built-In-Test

The DNA-AO-319-420, DNR-AO-319-420 and DNF-AO-319-420 are fully isolated, high-precision, 8-channel analog current output boards compatible with UEI’s popular “Cube”, RACKtangle and FLATRACK I/O chassis respectively. The boards offer full 16-bit resolution and guarantee monotonicity over the entire operating temperature range. Each DNx-AO-319-420 channel provides an output range of 4-20 mA (sinking). For applications requiring a sourcing output, please refer to the DNx-AO-318-020 and DNx-AO-318-024. For applications requiring voltage outputs please refer to the DNx-AO-308 or DNx-AO-318 series boards.

The DNx-AO-319-420 provides extensive built-in-test diagnostics. An on-board A/D converter on each channel allows the user to monitor both output voltage and current. A solid state relay on each output allows theD/A channel to be disconnected from the field I/O so that a complete board self-test can be completed without driving the circuitry connected to the outputs. This relay automatically disconnects the D/A output in the event of an external fault condition such as a short to ground or a DC power supply. The output relay may also be opened to simulate an open circuit/broken cable failure.

All 8 channels may be configured to update simultaneously, or they maybe updated one at a time as data is written. A 1024 sample FIFO allows each D/A to be updated at 10 kHz without data loss. Note that the output circuit only sinks current. Settling time for current increases will be low, but settling time for current decreases is largely set by the reactance of the sensor/cable combination (essentially a pull-up configuration).

Software included with the DNx-AO-319-420 provides a comprehensive, yet easy-to-use API that supports all popular Windows programming languages as well as supporting programmers using Linux and most real-time operating systems including QNX, RTX, VXworks, and more. Finally, the UEIDAQ Framework supplies complete support for those creating applications in data acquisition software packages such asLabVIEW, MATLAB/Simulink, or any application which supports ActiveXor OPC servers.

The DNx-AO-319-420 is a member of UEI's popular Guardian series, which provide high levels of user diagnostics. The AO-319-420 board provides voltage, current and temperature monitoring, field disconnect functionality, and programmable circuit breakers.