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What are possible causes for nSt status?

Issue:
What are possible causes for nSt on the Altivar drives?

Product Line:
Altivar ATV Drive line

Environment:
All

Cause:
Drive will not run.

Resolution:
NST is a drive freewheel state.  It is not a fault.  If the drive is in an NST state you can not run the drive in local or remote mode.

1:) 3 wire control:  check to see if NC stop on LI1 is open to +24vdc.
2:) 2 wire control:  check to see if the 2 wire type is level control or check to see if there is a run command on LI1 during power up.
3:) NST assigned as an logic input and that input is open.
4:) Stop button has been pushed on the local face or remote HMI and the drive is being commanded in terminal mode. 
5:) Drive is an CIA402 (DSP402) drive com NET command mode and is not received the proper commands to go to the RDY or RUN state.
6:) Any drop in +24V supply on the drive can cause NST.
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