harryting
Lifetime Supporting Member
So, I need a RS485 Modbus slave to do some testing.
Well, since I don't have any RS485 Modbus Slave sitting around but does have a Micrologix 1100, I went ahead and attempted to make it work.
Also, since I don't have a 1763-NC01 cable, which looks to me like a standard breakout, I'm using a 1761-CBL-PM02 mini-din to DB9 cable. Here's where I ran into some confusion. The RS485 2-wire should go on pin 4 and 5 of the NC01 which corrospond to pin 1 and 8 on the mini-Din. However, looking at the pinout for the PM02, pin 1 and 8 shows as 24V and GND, which makes no sense. Maybe it's only 24V/GND if it's configured as a RS232 instead of RS485?
Well, since I don't have any RS485 Modbus Slave sitting around but does have a Micrologix 1100, I went ahead and attempted to make it work.
Also, since I don't have a 1763-NC01 cable, which looks to me like a standard breakout, I'm using a 1761-CBL-PM02 mini-din to DB9 cable. Here's where I ran into some confusion. The RS485 2-wire should go on pin 4 and 5 of the NC01 which corrospond to pin 1 and 8 on the mini-Din. However, looking at the pinout for the PM02, pin 1 and 8 shows as 24V and GND, which makes no sense. Maybe it's only 24V/GND if it's configured as a RS232 instead of RS485?