FX2N series in the analog special function module: FX2N-2AD (2 channel analog input), FX2N-4AD (4–channel analog input), the FX2N-8AD (8 channel analog input), FX2N-4AD-PT (4 channel RTD input directly), FX2N-4AD-TC (4–channel thermocouple direct input), FX2N-2DA (2 channel analog output), FX2N-4DA (4–channel analog output) and FX2N-2LC (2–way temperature PID control module).
Following introduces common analog input module FX2N-4AD.
1. Overview of FX-4AD
FX-4AD analog input module is the Special FX series analog input modules. The module has 4 input channel (CH), input transformation, where you can select the voltage or current input state. When the input voltage, input signal range for DC – 10~+ 10V input impedance 200k ω, resolution of 5mV for current input, the input signal range is ~+20mA, input impedance 250 ω, resolution of 20 μA.
FX-4AD will receive the analog signals into a 12-bit binary numbers, and saved as a complement to the 16-bit data registers, numeric range is -2048~+ 2047. Its transmission rate for 15ms/K, precision for 1% of range.
FX-4AD power supply DC24V, photoelectric isolation between analogue and digital technology, but no isolation between channels. FX-4AD consumption of PLC main unit or the active extension unit slot 5V power supply current of 30mA. FX-4AD takes up the basic unit 8 image form, namely 8 I/O points in software, in calculating the 8 PLC I/O can be calculated as a PLC input points.
2. FX-4AD wiring
FX-4AD the wiring as shown in Figure 6-29, analog input signal used in twisted-pair shielded cable connected to the FX-4AD, the cable should be kept away from power lines or other conductor that may cause electrical interference. If the input voltage fluctuations or external wiring of electrical interference, you can access a 0.1 µ F~0.47 µ f (25V) capacitor. If it is a current input terminal V+ and I+ should be connected. FX2N-4AD earth terminal connected to the earth terminal PLC main unit, if there is too much electrical interference, then the shell side FX-4AD and FG earth terminal is connected.