Sampling Processing - Mitsubishi Electric MELSEC iQ-R User Manual

Sampling processing

Common
Analog input values are converted at each sampling cycle and stored in the buffer memory as digital output values. The
conversion cycle varies depending on the mode.
In the normal mode
The conversion cycle in the normal mode is the sampling cycle.
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.
Ex.
When the A/D conversion is enabled for CH1 and CH2 in the normal mode (medium speed: 10s/CH), the conversion cycle is
20s (10s  2). In this case, digital output values and digital operation values of CH1 and CH2 are updated every 10s.
A/D conversion processing
of the A/D converter module
'CH1 Digital output value'
(Un\G400) and
'CH1 Digital operation value'
(Un\G402)
'CH2 Digital output value'
(Un\G600) and
'CH2 Digital operation value'
(Un\G602)
■Precautions for using the normal mode (high speed: 1s/CH)
If CH Logging enable/disable setting is set to High speed continuous logging (2) for any channel, the digital operation values
are simultaneously updated in all channels at intervals of 5ms.
1 FUNCTIONS
24
1.5 A/D Conversion Method
Conversion cycle (20μs)
Sampling cycle Sampling cycle
(10μs) for CH1 (10μs) for CH2
A/D conversion A/D conversion
processing processing
for CH1 for CH2
10000
5000
Conversion cycle (20μs)
Sampling cycle Sampling cycle
(10μs) for CH1 (10μs) for CH2
A/D conversion A/D conversion
processing processing
for CH1 for CH2
12000 14000
6000