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Either (1) the limit switch is malfunctioning, or (2) the polarity of the limit switch has changed. There is an axis parameter, called LimitLevelMask, that sets the polarity of the limit switch. This tells us if we should throw the fault based on whether the signal is active high or active low for that limit.

Please look over the documentation for the LimitLevelMask in the NView help file. This parameter will most likely need to be flipped, as this parameter states whether we look for the limit switch input to be active high or active low. Either that, or the limit switch may be damaged. To diagnose, you can monitor the status of the limit switches using our NStat utility. Look under the Diagnostics tab and you will see CCW and CW, and the state of the switch, H (high) or L (low). If you manually move the axes into the limit switches, you can see the H or the L toggle. If it doesn't toggle, the switch may be damaged. If it does, then you simply need to flip the LimitLevelMask parameter.

If you do not have limit switches, then simply flip the bits in the LimitLevelMask axis parameter or remove the limit faults from the FaultMask.