TCP connection to SMC EX260-SEN closes after ~2-minutes

[Josep313]

I am running into an issue where after approximately 2-3 minutes, the connection to the hardware disconnects and I am unable to call SetAttributeSingle().

The current work-around has been to send some type of request to the hardware to keep alive.

See pseudocode:

while(true)
{
      var data = SolenoidData()
      // only set attributes if new data is present. data is the bit that needs to toggle on/off the solenoid 
      if (newData)
      {
         _ethernetIPClient.SetAttributeSingle(classID, instanceID, attributeID, data);
      }
    else 
      {
        _ = _ethernetIPClient.IdentityObject.SerialNumber; // do this so that connection is not lost after N minutes. 
      }

}

Any idea as to why the TCP client is disconnecting? Or is this a hardware issue where the device releases the TCP handle from the client?

[shinquapin]

I know it is several years later, but I am having a very similar issue with a SMC JXC918. I can still send implicit and explicit messages after two minutes, but when I run ForwardClose and UnRegisterSession I get a timeout error.