This is a new CNC lathe machine and was working fine two days ago, now there is “Spindle Speed not reach” alarm on the CNC controller as soon as turn on the machine power.

Input the M3 S500 or M4 S500 to start the spindle motor under MDI mode, but the spindle not run and alarm on CNC controller. Check other functions like tool changer, coolant pump, X and Z axes moving, they are fine.

Now check below steps:

1-      Is the outer wiring of the frequency inverter open circuit?

2-      Parameters of frequency inverter are set correct or not?

3-      Is the I/O board of the frequency inverter broken?

4-      I/O port of the CNC controller is fine or not?

In this case we found the speed reach signal of frequency inverter is loose with the speed reach detecting signal of the CNC controller, screw down the cables then the problem solved