Modbus - loss of communication

[emily001]

Hi, I'm doing a LabVIEW program for controlling 2 Variable Speed Drives, more specifically Abb ACS 880 and Abb ACS 580. I'm using the free Modbus library for the communication, with the Modbus TCP protocol. The program works fine for some time communicating with the both drives simultaneously, changing the operation mode, giving speed and torque references. After some minutes working the communication suddenly is lost. I would like to ask what might be the possible reasons for this loss of communication?

Thank you in advance.

Emilija

[elcalverado]

Hi Emilija,

Do you get any specific errors from the Modbus TCP subVIs? Do you lose connection to both drives simultaneously?

How are the drives connected over the network to the PC? Can you verify that the drives aren't losing power or losing connection on the network? I've had problems in the past where my PC's ethernet port would inconsistently lose connection to the network and drop communication to any network devices.