Calculating the temperature of each test point.
PLC programmable centralized control using output 4 ~ 20mA current signal 200 is deg.] C ~ deg.] C range -50
Pt100 and Pt100 temperature sensor temperature transmitter. The temperature transmitter Pt100 temperature sensor
PLC analog module, via the signal
-50 ℃ ~ 200 ℃, 4 to a corresponding output
current signal, i.e., corresponding to -50 ℃ output current of 4 mA, corresponding to 200 ℃ mA output current 20 is,
4AD analog module the analog input is set to 0 ~ 20ma, so when the input signal is 0 ~ 20mA
when the analog input terminal 4AD, 4AD 0-20ma current signal which is converted to a digital 0 to 4000.
4ma number corresponding to an amount of: 4mA = (4000 ÷ 20) * 4 = 800,) so that when the input current of 4 ~ 20 ma
analog 4AD when the input digital conversion 4AD from 800 to 4000. The measured temperature Tx
relationship AIW0 following Figure 1:
FX PLC program are as follows:
temperature calculation program
=(AIWX-6400)*250/(32000-6400)-50
To complete the read analog values, convert to engineering required magnitude.