Siemens's Industry Automation Division has expanded its SIMATIC top connect system cabling to include a compact optocoupler module for facilitating quick switching of high load currents of up to 4 amperes at 24 volts DC. The new unit is 134 millimeters wide and is a new addition to the SIMATIC top connect module family. These modules enable users to connect I/O components quickly and reliably to SIMATIC S7-300 Controller input/output modules. One of the big advantages of the optocoupler technology is its high switching frequency of up to 500 hertz - as compared to the mere 5 to 10 switching cycles per minute achieved by conventional relays.