Mitsubishi Electric R60AD8-G - A;D Conversion Method

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1 FUNCTIONS
1.4 A/D Conversion Method
1.4 A/D Conversion Method
An A/D conversion method can be set for each channel.
Sampling processing
This function converts analog input values to digital values at every sampling period and stores the digital output values in
buffer memory areas.
The sampling period is "Conversion speed (10ms)  number of conversion enabled channels".
Whether to enable or disable the A/D conversion can be set for each channel. Disabling the A/D conversion
for unused channels reduces the A/D conversion cycles.
Conversion cycle that applies when CH1 to CH3 is set to A/D conversion enabled
•10  3 = 30 (ms)
The conversion cycle is 30 (ms).
Digital output values and digital operation values of CH1 to CH3 are updated every 30ms.
Averaging processing
The A/D converter module performs the averaging processing on digital output values for each channel. The processed
values are stored in the buffer memory area.
The following three types of averaging processing are provided.
• Time average
• Count average
• Moving average
■Time average
The A/D converter module executes the A/D conversion for the setting time, and performs the averaging processing on the
total value excluding the maximum and the minimum values. The processed values are stored in the buffer memory area.
• Setting time
Set a value that satisfies the following condition.
Ex.
The following shows the lower limit value to be set for when CH1 to CH8 are used.
10 (ms)  8 (CH)  4 (times) = 320 (ms)
• Processing times
The number of processing times within the set time changes depending on the number of channels where the A/D conversion
is enabled.
Ex.
The following table shows the processing times with the setting below.
*1 Values after the decimal point are omitted.
Conversion is processed 6 times and the mean value is output.
Item Setting
Number of channels where the A/D conversion is enabled Four channels (CH1 to CH4)
Setting time 250ms
Lower limit value to be set ≥ Conversion speed × Number of conversion enabled channels × Minimum number of processing times (4 times)
Number of processing times =
Setting time
(Number of conversion enabled channels × Conversion speed)
= 6.25
*1
250
(4 × 10)