The HUB-Serial-4 is a rugged, industrial-grade, optically-isolated RS-232/485/422 Hub / Splitter, which can be used to expand 3-wire RS-232 or 4-wire RS-485 / RS-422 networks by splitting one network into four (star wiring), in turn increasing the maximum number of nodes and the distance covered by an RS-232 / RS-485 / RS-422 network. This industrial opto-isolated RS-232/RS-485/RS-422 Hub / Splitter operates within a temperature range of -40ºF to 185ºF (-40ºC to 85ºC), features 600W surge protection, 15kV ESD static protection and 2500V opto-isolation circuitry, which effectively protect your RS232 / RS485 / RS422 devices from ground loops, noise problems, transient surges, remote lightning and spikes. The unit comes with options for RS485, RS422, or RS232 input, for easy installation. It was designed so that data coming from the input (RS-232, RS-485, or RS-422) will transmit to all four loops of networks. However, each loop of RS232 / RS485 / RS422 devices will transmit data back to the input only, thus reducing any possible interference between each loop of the RS-232 / RS-485 / RS-422 devices. Also, the failure of any individual loop will not affect other loops, making the RS-232 / RS-485 / RS-422 networks more robust and reliable. The unit supports data rates up to 115.2K Baud and features data format auto-sensing and self-adjusting; therefore, no DIP switch, jumper settings, software drivers or flow control is required. A separate external 5VDC power supply is included in the package, and the product can be mounted directly on a wall or panel.