SOM1 - Expandable Serial Relay Unit

SOM1 - Expandable Serial Relay Unit
Zoom  Zoom
Our Price:  £49.00(£58.80 Inc. VAT)
Add UK 12V DC Mains PSU:  
Add EU 12V DC Mains PSU:  
Add RS232 Null Modem Cable:  

Digital Outputs:  4


No stock, discontinued  

No stock, discontinued

A low cost general purpose Relay-output board for connection to a PC's serial port. Expandable to over 256 units with up to 1024 relays from a single serial port. Complete with free software.

Special Offer:  Discounts of 7%, 10%, 12.5% and 15% are available when you order 10, 25, 50 and 100 items or more of this product.

  • 4 Independently Controlled Relays on each Module
  • Switches 2 Amps dc/50 Volt ac (1 Amp inductive)
  • Up to 256 Modules on a Single Serial Port connected bo on-board RS485 converter
  • Free Software
  • Voltage Free Changeover Relay Contacts
  • Up to 1024 Relays Controlled from a Single Serial Port
  • Versatile Inter-unit Wiring
  • Compact Size
  • VB and Delphi demo available
  • Dimensions - 95mm x 80mm 
  • Power: 10 to 15 Volts d.c. @ 100mA

The SOM1 Serial Output Module is designed to be used with PCs and compatibles. Each module has 4 independent single pole changeover relays which can be independently addressed from the PC. The standard RS232 serial output is converted to RS485 by the first module and this is used to drive subsequent modules. Each module may be allocated one of 256 addresses, thus allowing for control of 1024 relays. Addresses are selected using an 8 way DIL switch and more than one module can have the same address. This will allow several relays to be controlled simultaneously.

Modules can be physically placed in positions remote from the PC. The link from the PC Serial Port to the first module is restricted to approximately 50 metres. After that modules can be located as much as 200 metres apart. Connection between the PC and the first module would normally use a standard null terminated modem lead connected to the 9 pin 'D' connector. From the first module to subsequent units twin screened cable is recommended with connections to the screw terminal block provided. Inter-module wiring may be either parallel or serial with 'T' junctions as required. Cable impedence matching may be selected by on board links.

The SOM1 is supported by FREE windows based software. To control the module there is no need to write any code.

  • Manual control of each relay via "Toggle" switch
  • virtual LED indication of relay status
  • Timer function - each relay can be independantly made to switch on or off at timed periods
  • unlimited on/off times can be programmed
  • resolution down to 1 second
  • different times for each day if required
  • time settings can be saved in a setup file

This program has been written using ProfiLab - a low cost graphical programming package designed for data acquisition and control applications. No programing experience is needed, programs are written by connecting function blocks together with wires. Professional user panels can be designed with custom controls, and the whole program can be compiled into a stand-alone executable file, with no run-time penalties.


User Manual >>

Software >>


Continue ShoppingTell a Friend