Hello,

Z axis either Servo or pulse enable signals are reset. Check DB3x.DBX2.1 or DB3x.DBX21.7 signals in PLC logic.

Please attach the detail snap of fault message displayed on OP so that correct help could be provided. 

You did not know if your 840D has "safety integrated " ? if it is, you need check #2--see below or call OEM or Siemens service 

If you have ability to use PLC program troubleshooting, check #1--below

If NOT at all, you need to call Siemens service,

But you can do something before you make the  call  --such as machine working story , how long this problem happened, seems they happen to every axis  --you can think some common cause, --check the electrical drawing to find some hints

dukhia

21612 zz axis enable reset, 21612 xx axis enable reset, 21612 s/c enable reset in 840d system on cnc spinning machine frequently, kindly suggest

...sent from App