Modbus RS232 to RS485 converted
Modbus RS232 to RS485 converted
(OP)
I have a PLC that talks Modbus. I am going to use Modscan software running on my laptop (master), to pull data form the PLC (for initial testing purposes). The PLC have 3 terminal blocks for communications (+,- and shield).
In order for me to connect from my laptop comports (comm1, RJ485 to USB) to the PLC, I guess I will need a converter (RS232/RS485 or USB/RS485).
Since this setup is for testing only, I would like to buy a very basic converter. Can I make the converter myself?
Thanks
In order for me to connect from my laptop comports (comm1, RJ485 to USB) to the PLC, I guess I will need a converter (RS232/RS485 or USB/RS485).
Since this setup is for testing only, I would like to buy a very basic converter. Can I make the converter myself?
Thanks





RE: Modbus RS232 to RS485 converted
If productivity is your (or your employer's) goal, then buy the tool and get the job done.
If serial communications is your hobby, have at a design.
Dan
RE: Modbus RS232 to RS485 converted
RE: Modbus RS232 to RS485 converted
I use a little 9 pin to terminal strip type of convertor by B&B electronics, part number 485SD9TB, port powered and works very well, don't know if you could build one for the price they charge.
Regards,
RE: Modbus RS232 to RS485 converted
Some port powered converters have no provision (no terminals) for external power. My opinion: avoid those at all costs.
I've never tried to connect 23 to 485 without a converter. Maybe I'll give that a shot sometime on a benchtop.
Dan