AD/DA mixed module Features

1. A/D conversion method
   Sampling process
   This process makes it possible to sequentially convert analog values to digital value by A/S conversion and store it in buffer memory. Sampling process is performed with a frequency of 2.1 ms regardless of the number of channels in use.

Averaging process
This process calculates average value from sum of sampled AD converted values by the number of average processing times and then stores it into buffer memory. In this case, if average processing time is already set, the system converts AD converted values inputted based on set frequency not directly taking AD converted value and uses it to calculate averaging for the number of times. Digits after decimal occurred from AD conversion will be discarded. Set range for average calculation is 1~ 255 times for number and 0~255(X10) ms for average time. And if the value for time average is set to ‘0’, the system performs only number of times for sampling data.

In the event that average value for number of time is set to 10 times,
The system calculates average by receiving sampling process data (2.1ms) 10 times. In other words, average value for signals which is inputted for 21ms is outputted as AD converted value. In this case, the frequency for updating data is 2.1ms which is sampling processing time.

In the event that average processing for number of times is set to 10 times and that of time is set to 5(50ms).
Average processing is performed in a way that data is sampled every 50 ms and the system receives this value 10 times. In other words, average value for signal which is inputted for 500 ms is outputted as AD converted value. In this case, the frequency of updating data is 50ms which is average processing time.
30 X (4 X 5) = 600(ms)

2. Digital output value setting
   When Digital output value is saved into Buffer memory, you can select signed value 16 bit data (-32000~32000) or unsigned value 16 bit data (0~16000)

3.Precise value
The system displays analogue signals coming to each channel separately from digital output value. The measured value can be checked without additional data processing. Displaying range for the measured value for each input signal is referred as following.

4.Percentile value
Converted input value for each channel is displayed by percentage (0~10000) compared to whole input signal range.

5.D/A conversion Enable /Disable settings
It is used to set D/A conversion Enable/Disable for each output channel.
If unused channel is set to be Disable for switching channel, offset value is outputted.(4mA or –10V)
The conversion speed is at constant regardless of conversion Enable/Disable settings

6.Analog output Clear/Hold settings
It is used to hold or clear out analog value when PLC status is Stop mode or Error.

7.Offset/Gain settings
When digital input value is 0~16000 or -8000~8000, analog output can be calibrated to 4~20mA or -10~10V.

8.Digital output settings
When digital input value is saved to Buffer memory, the range 0~16000 or –8000~8000 can be selected..

9.D/A output Enable/Disable
It is used to select output D/A conversion value or offset value to each output channel.
The conversion speed is at constant regardless of Output Enable/Disable settings.

• Note) When D/A output is set to be Disabled although D/A conversion is set to Enable for each channel, D/A converted value is not normally outputted, instead the offset value (4mA or -10V) value is outputted. Because D/A output Enable/Disable is not saved, make sure to set corresponding channel for each Enable/Disable (User Program Memory address 23) to Enable (1) using TO command in the first scan to use channels.