USB relay units switch 3A of mains current

The UDIN range consists of a USB interface, a micro-controller and relay outputs and/or opto-isolator inputs. Each unit is controlled by simple ASCII commands and the USB interface handles the USB protocols and presents the ASCII commands to the micro-controller as serial data. The micro-controller then uses the commands to control the relays or report back input status.

There are four models in the range. The UDIN-8R has eight relays, the UDIN-8I has eight opto-isolated inputs and the UDIN-44 has four relays and four opto-isolated inputs. There is also the UDIN-16A that has four mains-rated 16A relays and four opto-isolated inputs.

Most software packages that can send or receive ASCII data to an RS232 port should be able to control the UDIN range. The UDIN units comes with a virtual Com port driver, which installs a virtual' Com port on the PC. Software can then send and receive ASCII data to and from this virtual Com port and, hence, to the UDIN unit. Typical packages that can be used include Windows HyperTerminal (and most other terminal emulator packages), data acquisition packages such as Profilab, DAQFactory, LabVIEW, DasyLab, VEE, TestPoint etc, and also most SCADA packages.

Alternatively, programmers can bypass the VCP route and use direct .DLL function calls. The UDIN units are supplied with a test application complete with all source code. Drivers are available for the Windows operating system, Linux, MAC and Win CE.NET.