USB RLY08 switching controller for local and remote usage
General info :
The RLY08 relay module is a very interestin
g device to switch all kinds of things from your
computer. And it isn’t as expensive at all like a lot of other modules from other brands.
The module comes with a test application that is very basic, so it would have been nice to
have a better relay cont
roller application. Dirk Claessens wrote such a program.
It was at first designed to switch different receiving antennas in a radio enthusiast’s shack.
But it can off course be used for all kinds of thing that must be switched on and off.
nd use is simple and straightforward. There is no need to download a dedicated
driver. Although the above mentioned General Info link contains a link to a driver page,
Windows XP, Vista and 7
the device smoothly.
To know which COM port it has
been assigned to, take a look in Device Manager by right
click on “Computer” and “Device Manager”, or go to Properties, Hardware tab, and Device
Manager in Windows XP). In the Category “Ports (COM & LPT)” you will find a new entry
called “USB Serial Port”
and will show the Com Port number.
Now launch at first, as a test, the original
USB RLY08 TEST
program to see if everything
Now let’s take a closer look at the more a
ppropriate RLY08 controller program that can be
The application doesn’t need to be installed. You can just put it anywhere on your computer,
but keep in mind that the logged on user must have rights to
write the folder where the
program is stored. So if you are using Vista or Windows 7, it might be wise to put it f.e. in
RLY08” instead of storing it under Program Files.
Once done this, after launching the RLY08.exe, you will see this user interfac
First you have to choose the correct Com port and click on the “Open” button to activate the
application. Clicking on the checkboxes will activate the relays and the LED next to it will
clicking on the row behind a checkbox will call
up window to edit labels that will
appear next to the checkboxes and will be kept in an ini file so that they are remembered
after closing the application.
The Log checkbox shows the commands transferred to the relay device.
All Off” is self
It is also possible to use the device remotely over a LAN or via the internet.
You can test it locally by launching the RLY08 controller twice on the same computer.
At the Slave side (the side where the relay device is connected to the com
puter) you have to
choose the com port first and click on the Open button. Then you can click on the Slave
button and then on the Start button. The listening port is “50035” by default. If it is already in
use on your computer you will get an error pop
. Choose another one but use a high
number (max is 65535). Of course you will have to alter the port number at the Master side
as well. Don’t forget to click on the Slave’s Start button, the Led above the Slave button will
turn into orange, indicating the
slave is ready to accept connections from the master.
Now launch a second instance of the application while testing it on the same computer. Click
on Master. In the Slave’s Host Name/IP field you can leave “localhost” for local testing.
the Start button of the Master’s application and if everything is configured correctly,
the Led’s at the Slave and Master will turn into green. Your firewall might ask if access is
If you want to use it over a LAN, put in your local ip addres
s (something like 18.104.22.168
lasts number will most probably be different). You can find you local IP number by launching
the command “ipconfig” from the command prompt, or by looking at the settings of your
router. Be sure to use the
If you want to use it over the internet you have to fill out the slave’s external IP address. Go
and copy/paste that row of
numbers into the “Slave Host
Alternatively, and also from the slave location, go to your router's configuration interface and
look up the router's
(WAN) IP. Note that you
use your router's internal IP
(192.168.x.y) over the internet!)
You have to
open port 50035
in the router at the
location as well (allow TCP traffic).
No straight forward instructions can be given here while this is different for every brand. Look
into your router’s manual.
Also here, your firewall might also ask if acce
ss is allowed. Usage from the Master side is the
same as locally, but you have to add the labels here as well.
Tip : If you want to configure the settings on the Slave’s computer remotely, it might be
interesting to use Teamviewer.
Example of a RLY08 in use to switch antennas.
Application by Dirk Claessens
Manual : Guido Schotmans.