4 channel computer serial port temperature monitor and relay controller with four inputs for the Dallas DS18S20 (or DS18B20) digital thermometer sensors. The four relay channels provide output control and are independent of the sensor channels giving you the flexibility to setup the linkage any way you choose.
Commands for reading temperature or controlling relays are sent via the RS232 interface using simple text strings. The board can be controlled with a simple terminal or communications program (such as Windows HyperTerminal) or our free Windows application (see below for details).
Each output is capable of switching resistive loads up to 48Vac/24Vdc @ 5 amps max and have high quality detachable screw terminal block connectors. (*NB The relays are rated to switch up to 240Vac mains voltage but the exposed screw terminal block heads would need to be placed inside a suitable enclosure to prevent exposure to hazardous voltages).
All components provided including one temperature sensor, a high quality case with pre-punched and silk screened front and rear panels to give the kit a professional and attractive finish as shown in the photos. High quality DS PTH PCB.Application Ideas
This board is an ideal use for old computers - continuous temperature data monitoring and control. A few ideas of how this circuit can be used as given below (additional equipment/software may be required):