The following are some basic facts about input loop power sources: The input module usually isn't a loop power source. Although 120V is common for digital loops, other voltages are also used. There ...

Digital/binary sensors and switches are essential for signal monitoring and system control in industrial control, industrial automation, motor control, and process automation. All the sensors’ outputs ...

The PuffinPLC Project is an effort to produce a Linux-based GNU Public Licensed Programmable Logic Controller (PLC). PLCs were developed in the 1960s to replace the complex electrical relay circuits ...

In our previous issue, we noted that the first step in troubleshooting digital input modules is to verify the power source of each loop. If input power is missing, the causes can be such things as ...