Modbus over RS-485 half duplex

[bmcoleman]

I’m currently trying to set up an Anybus HMS-EN2SE-R serial to Ethernet IP linking device. I would like to read the data from another device (easygen) via Modbus over RS-485 half duplex. I attached the pinout of the device I’m trying to read from below and the pinout of the HMS-EN2SE-R. I believe I have configured the devices correctly on each end, but I’m unsure of the pinouts. Do I need to connect the 5V pin if I’m just reading from the easygen? Would I connect the RS485+/- pins on the anybus to the TX pins 2 and 7 on the easygen? And then is it + to - and vice versa? Do I need to change any settings on the Anybus that I’m using half duplex?

Thanks

[kyle_HMS]

On RS-485 you connect +<-> + and - <-> - so it looks like pin 9 to 9 and pin 4 to 8 it looks like.

As far as 5V goes, you would connect that to pin 8 with a 470 ohm resistor:

Also, make sure you are using 120 ohm resistors to terminate the ends of the bus.