ADLINK ND-6067 - Manual (Page 67)

65
4
Analog Output Modules
4.1 Overview of ND-6021
ND-6021 is an analog signal output module. It receives the digital command
from host computer through RS-485 network. The format of the digital value can
be engineering units, hexdecimal format or percentage of full-scale range(FSR).
A microprocessor is used to convert the digital command to digital value to send
to DAC. The DAC converts the digital value into analog form. The analog output
can be either voltage or current output.
The ND-6021 is designed for safety. It provides many safety functions such as
isolation, watchdog, and power on safe value. The opto-isolators provide
5000Vrms isolation voltage to isolate the digital section and the remote
controlled analog equipments. The damage of power surges is avoided.
Another safety fucntion is the watchdog. Whenever the host is loss contact with
the remoted NuDAM module, or the micro-processor is down, the module will
reset itself and send the safety value to the analog output therefore the industry
safety is guarantee. The safety value / power-up value can be set by
configuration software.
The analog output can be readback through the module‘s ADC. which can
monitor the ’real‘ output of the device. The host can check the digital command
and the real output to avoid short circuits. The slew rate of the output signal is
also controllable by software.
4.1.1 Features of ND-6021