Fanuc M410 i R 30iA - Ethernet No Robot Heartbeat

Good Evening ,

I have a Fanuc M 410i R30 iA , that is communicating with a CompactLogix L32. In the CompactLogix program there is a Robot Heartbeat timer . It is timing out causing a communication fault. I am able to ping that IP address fine for the robot . Would you folks know where this heartbeat comes from , and what could cause this communication to fail. It seems like if I am able to ping the robot we should have a clock pulse .

Thanks , I am stuck again .

Apparently it was the door switch at the base of the robot. Never thought that would effect the communication pulse .