Difference Conversion Function - Mitsubishi L Series User Manual

8.13

Difference Conversion Function

The scaling value (digital operation value) at the start of this function is treated as 0 (reference value). Thereafter,
values that increase or decrease from the reference value are stored in the buffer memory.
CH Difference conversion
trigger
(Un\G172 to Un\G175)
CH Scaling value
(digital operation value)
CH Difference conversion
reference value
(Un\G180 to Un\G183)
CH Scaling value
(digital operation value)
(Un\G54 to Un\G57)
CH Difference conversion
status flag
(Un\G190 to Un\G193)
(1) Operation of the difference conversion function
When the difference conversion starts, the scaling value (digital operation value) at that time (the data stored
inside the A/D converter module before difference conversion) is determined as the difference conversion
reference value. The value acquired by subtracting the difference conversion reference value from the scaling
value (digital operation value) is stored in CH
Therefore, CH
the scaling value (digital operation value) equals to the difference conversion reference value at the start)
Scaling value (digital operation value)
after difference conversion
(2) How to use difference conversion
(a) Starting difference conversion
1.
Change CH
request (1).
The rise of No request (0) → Trigger request (1) is detected as a trigger. When the trigger is detected, the
scaling value (digital operation value) at the start is output to the difference conversion reference value.
The value acquired by subtracting the difference conversion reference value from the scaling value (digital
operation value) is stored in CH
value is stored, CH
difference (1).
94
Scaling value
(digital operation value)
20000
10000
7500
2500
0
-2500
No request (0)
6000 7500 10000 10000
0
6000
Not converted (0)
Scaling value (digital operation value) (Un\G54 to Un\G57) at the start of this function is 0. (since
=
(digital operation value)
Difference conversion trigger (Un\G172 to Un\G175) from No request (0) to Trigger
Difference conversion status flag (Un\G190 to Un\G193) changes to Converting
CH
(digital operation value)
(Un\G54 to Un\G57)
Trigger request (1)
7500
0 2500 2500
Converting difference (1)
Scaling value (digital operation value) (Un\G54 to Un\G57).
Scaling value
- Difference conversion reference value
Scaling value (digital operation value) (Un\G54 to Un\G57). After the
Scaling value
Time
No request (0)
7500 7500
7500 7500
Not converted (0)