Mitsubishi Electric MELSEC-FX3S Series - Page 384

I-10
2 Specifications
2.4 A/D Conversion Time
FX 3S /FX 3G /FX 3GC /FX 3U /FX 3UC PLC User's Manual - Analog Control Edition
FX 3U -4AD-PT-ADP (4-channel Platinum Resistance Thermometer Data Input)
2.4.2 When connected to a FX3G/FX3GC 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 the 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 adapters."
FX3G/FX3GC Series PLC
FX 3U-4AD-PT-ADP
1st
FX3U-4AD-PT-ADP
2nd
A/D
conversion
250 s/4ch
A/D
conversion
250 s/4ch
Digital value reading
A/D conversion start
command
A/D conversion start
command
END instruction
Sequence
program
Digital value reading