The CM4-PRO has two isolated digital input detection interfaces
Digital Input
CM4-Pro has two channels of digital input detection with isolation. There are only two states of digital input: high level and low level. There are two connection methods for digital input signals, namely dry contact (passive) connection and wet contact (active) connection. Wet Contact The connection mode of wet contact needs external power supply, the input is active signal, the positive electrode is connected to the DIN+ port of equipment, and the negative electrode is connected to the DIN- port of equipment. When DIN+ and DIN- are connected and the level signal is greater than 3V, the internal optical coupler of DI port is connected, that is, the module considers the input signal as low level; when DIN+ and DIN- are disconnected, the internal optical coupler of DI port is connected, that is, the module considers the input signal as high level.
In the field of industrial control, three wire PNP type and NPN type sensors are the most common. Among the three wires, usually brown represents the positive electrode (VCC), blue represents the negative electrode (GND), and black represents the signal output terminal (OUT). PNP type sensors are also known as source input mode sensors. When a signal is triggered, the OUT signal terminal outputs a high level. The connection diagram of PNP type sensor is as follows.
If you do not use an external power supply to power the sensor, you can use the Vout provided by CM4 Industrial for power supply. The connection diagram for PNP type sensors using Vout power supply is as follows:
WARN: Vout can only provide 12V power output. NPN type sensors are also known as sinking input mode sensors. When a signal is triggered, the OUT signal terminal outputs a low level. The connection diagram of NPN type sensor is as follows.
If you do not use an external power supply to power the sensor, you can use the Vout provided by CM4 Industrial for power supply. The connection diagram for NPN type sensors using Vout power supply is as follows:
WARN: You can only provide 12V power output. Dry Contact The input signal of dry contact connection mode is passive switching signal. The change of input state can be detected by disconnecting or shorting the DI and COM port.
