Hi. After playing around with the PLC and motors for a while with no problem, I encountered the same problem when I try to communicate with 4 MD888 using RS485. Trilogi can load using 9 pin to 485 while the motor is off but the same problem came back to haunt me when the motor is on. However, when I try to communicate with individual 888 using 9 pin cable, all works fine. Tried grounding the 9 pin port of the Auto 485 but the same problem still occurs. Any way to solve the problem?