Model description:
ST: Standard transistor type, the output is a 24V transistor, which can only be connected to 24V, and the ST's working power supply is also 24V;
SR: The working power supply is 220V, and the output can be either AC or DC;
DC/DC /DC: Working power supply, input power supply (electrical signal to PLC after the limit is reached), output power supply;
input wiring description:
ST20 is 12 inputs and 8 outputs, the common end of 12 inputs is 1M, if 1M is connected to negative , Then 0.0~1.3 needs to be connected to the positive, if 1M is connected to the positive, the other end must be connected to the negative
output. Wiring instructions:
Because it is a transistor output, then 2L+ is connected to 24V+, 2L- is connected to 24V-,Q0.0~Q0.7 will output a high level once there is output, so the other end must be connected to negative, Smart transistor types all output high level, connected to one end of the load, and the other end of the load must be connected to negative. L+ and M are 24V power supplies output by PLC, which are equivalent to a switching power supply. They are generally used for analog modules and have strong anti-interference ability. It will be more dangerous to supply power to some high-power electrical equipment such as sensors, because the external electricity is more Complicated, it is possible to burn the PLC. Of course , it is also possible to use the output of L+ and M to supply 2L+ and 2M , but for safety reasons, we usually do not do this.
Another model
Model description:
R in SR stands for relay, AC/DC/relay respectively correspond to: working power supply, output power supply, output type is the relay
input wiring: exactly the same as ST,
output wiring description:
0~3 can be connected to 24V DC at the same time 4 ~ 7 can be connected to 220V alternating current, because these are two sets of common terminals related to each department. The PLC will also output a 24V DC.
