Hi Folks.
In a previous life I used Allen Bradley SLC-500's to teach electrical apprentices the basics of PLC's. These were programmed using RSLinx and RSLogix installed on a laptop and communicating through an RS232 cable. I now run Node Red on a Raspberry Pi and was wondering if there is anyway to integrate Node Red into the SLC500 in some way. I know these PLC's are obsolete but I have one at home and would love to tinker with it. By the way I still have a laptop running Windows XP which has a licenced copy of RSLinx and RSLogix installed.
Thoughts?
What protocols does the plc have available? EtherNet/IP? DF1? Modbus RTU?
The SLC 5/03 CPU has sockets for RS232 which is used for programming with the laptop and there is a socket that looks like an ethernet port (but I dont think its a regular ethernet configuration) called DH485
You are right. The RJ45 is not Ethernet. It runs a serial network called "Data Highway 485" (DH485) which, if i recall, is a proprietary AB protocol. The RS232 port however can be setup to communicate on a protocol known as DF1 which is easy to connect with an ordinary serial port. The DH485 port requires a converter e.g. 1747-UIC (a USB to DH485).
You could try one of the 2 DF1 offerings in the node catalog:
https://flows.nodered.org/search?term=DF1&type=node
Yes Steve I seem to recall one of my colleagues using a 1747-UIC adapter with some success, I'll look into it.
If you use the serial port (RS232) you can make (probably buy) a cable much cheaper & the DF1 protocol is quite simple to implement (and there are existing pre-build nodes already implementing the DF1 protocol as linked above).
I dont think there are any nodes available to "speak" to Data Highway and I am not certain the protocol can be changed to DF1 on the DH485 port.
Testing my old knowledge here …
If you have a 5/03, 5/04 processor I think they support Modbus RTU out the serial port. Might investigate that avenue…
Cheers!
