4-20 mA sensors Wilcoxon Research 4-20 mA vibration sensors are an accelerometer and vibration transmitter combined in one rugged, industrial housing. They provide a 4-20 mA output signal proportional to the overall vibration level. The 4-20 mA output is commonly accepted by process control systems such as a PLC, DCS or SCADA system, for cost-effective continuous vibration monitoring. If you already have a process control system that accepts 4-20 mA inputs - like a PLC or DCS network - you are already taking data points on pressure, temperature, or maybe flow. You can send vibration data to your PLC or DCS as well. By connecting into process control systems, you are able to perform simplified condition based maintenance on machinery without the investment and learning curve associated with traditional vibration monitoring systems with data collection boxes and custom software.