What is nSt on an Altivar Process Drive display?


09 March 2022

nSt on an Altivar Process Drive.

Product Line:
Altivar Process Drive (ATV630, ATV930, ATV650, ATV950, ATV660, ATV960, ATV680, ATV980)

All Product Lines for the Altivar Process Drive

NST = Drive state for freewheel stop.

Troubleshooting tips:

  • Check Freewheel Stop Assignment. [Complete settings] [Generic functions] [Stop configuration] [Freewheel stop ass.] If a digital input is assigned, check the state of that input. 
  • Pushing the "STOP" key on the HMI will trigger nSt if your run command is coming from the terminal inputs.  Cycle drive power to clear it.
  • If a run command is present when power is applied to the drive and tCt (2 wire type) is not set to LEL (level), nSt will be triggered.
    • Check 2 wire type [Complete settings] [Command and Reference] [2-wire type]
  • If drive is in a Network setting and the parameter Control Mode [CHCF] is set to Separate or Not Separate then nSt may show until a run command is given.
  • Measure 24V to COM and make sure you have 24Vdc present.
  • Check 4-20mA Loss setting and see if it's set to freewheel stop.
  • Check External Error Response [Complete Settings] [Error/Warning Handling [External error] and see if it's set to freewheel stop.