Mitsubishi Electronics MELSEC-F Manuel D’Utilisation

Page de 504
C-9
2 Specifications
2.4 A/D Conversion Time
FX
3G
/FX
3U
/FX
3UC
 PLC User's Manual - Analog Control Edition
FX
3U
-4AD-ADP (4-channel analog Input)
A
Comm
on I
te
ms
B
FX
3U
-4AD
FX
3UC
-4
A
D
C
FX
3U
-4A
D
-A
D
P
D
FX
3G
-2A
D
-BD
E
FX
3U
-4DA
F
FX
3U
-4D
A
-AD
P
G
FX
3G
-1D
A
-BD
H
FX
3U
-3
A-
ADP
I
FX
3U
-4
A
D
-P
T
       
         
   -
A
D
P
J
FX
3U
-4A
D
-P
TW
     
        
      -
A
D
P
2.4.2
When connected to a FX
3G
 PLC
1. A/D conversion and special data register update timing
A/D conversion is performed at every scan time of the PLC.
During execution of END instruction, the PLC performs A/D conversion, reads out the A/D converted data,
and then writes the data in the special data registers.
2. A/D conversion during PLC STOP
Even if the PLC is stopped, A/D conversion will be performed and the special data registers will be updated.
3. If two analog special adapters are connected
During execution of the END instruction, data will be read out from all the connected adapters (in the order of
1st adapter 
→ 2nd adapter).
4. A/D conversion speed (data update time)
During execution of END instruction, the A/D converted data of all 4 channels will be read out in 250
μs, and
the data read out will be written to the special data registers.
END instruction execution time will be "250
μs × number of connected analog adapters."
FX
3G
 Series PLC
FX
3U
-4AD-ADP
1st
FX
3U
-4AD-ADP
2nd
A/D
conversion
250
μs/4ch
A/D
conversion
250
μs/4ch
Digital value reading
A/D conversion start
command
END instruction
Sequence
program
Digital value reading
A/D conversion start
command