Temperature Measurement - Mitsubishi MELSEC-F FX3U Series User Manual

FX /FX Series PLC User's Manual - Analog Control Edition
3U 3UC
FX -4AD-TC-ADP (4-channel Thermocouple Data Input)
3U
2.4 A/D Conversion Time
This section describes the A/D conversion time.
1. A/D conversion and special data register update timing
A/D conversion is performed at every arithmetic operation 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.
FX -4AD-TC-ADP
3U
A/D
conversion
200 µs/4ch
2. A/D conversion during stoppage of PLC
Even if the PLC is stopped, A/D conversion will be performed and the special data registers will be updated.
3. If two or more analog special adapters are connected
During execution of END instruction, data will be read out from all the connected adapters (in the order of 1st
adapter → 2nd adapter...4th adapter).
4. A/D conversion speed (data update time)
During execution of END instruction, the A/D converted data of 4 channels will be read out in 200µs, and the
data read out will be written in the special data registers.
END instruction execution time will be "200µs × number of connected adapters."
2.5

Temperature Measurement

To stabilize the temperature measurement, warm-up the system for 30 minutes or more after power-on.
F-8
FX -4AD-TC-ADP
3U
n'th
conversion
200 µs/4ch
1st
A/D conversion start
command
A/D
Digital value writing
A/D conversion start
command
Digital value writing
2 Specifications
2.4 A/D Conversion Time
FX /FX Series PLC
3U 3UC
Sequence
program
END instruction