Read DAC Limit Status

	Board ID is a unique number assigned by Measurement & Automation Explorer (MAX) used to send and receive commands and data to or from a specific NI motion controller.
	Ret Vect contains the reverse limits and forward limits, which are returned in one onboard variable: 0000 000R RRRR RRR0 0000 000F FFFF FFF0. Available return vectors include return data to the host (0xFF), return data to a variable (0x01 through 0x78), return data to an indirect variable (0x81 through 0xF8), and do not return data (0). Refer to Input and Return Vectors for more detailed information.
	error in (no error) describes error conditions that occur before this VI runs. The default input of this cluster is no error. If an error already occurred, this VI returns the value of error in in error out. The VI runs normally only if no incoming error exists. Otherwise, the VI passes the error in value to error out. The error in cluster contains the following parameters: status is TRUE if an error occurred before this VI was called, or FALSE if not. If status is TRUE, code is a nonzero error code. If status is FALSE, code is zero or a warning code. code is a number identifying an error or warning. If status is TRUE, code is a nonzero error code. If status is FALSE, code is zero or a warning code. Use the error handler VIs to look up the meaning of this code and display the corresponding error message. source is a string that indicates the origin of the error, if any. Typically, source is the name of the VI in which the error occurred.
	Negative Limits is a bitmap of the negative DAC torque limit status: DAC 1—If true, DAC output is at the negative limit. If false, the DAC output is above the negative limit. DAC 2—If true, DAC output is at the negative limit. If false, the DAC output is above the negative limit. DAC 3—If true, DAC output is at the negative limit. If false, the DAC output is above the negative limit. DAC 4—If true, DAC output is at the negative limit. If false, the DAC output is above the negative limit. DAC 5—If true, DAC output is at the negative limit. If false, the DAC output is above the negative limit. DAC 6—If true, DAC output is at the negative limit. If false, the DAC output is above the negative limit. DAC 7—If true, DAC output is at the negative limit. If false, the DAC output is above the negative limit. DAC 8—If true, DAC output is at the negative limit. If false, the DAC output is above the negative limit.
	Positive Limits is a bitmap of the positive DAC torque limit status: DAC 1—If true, DAC output is at the positive limit. If false, the DAC output is below the positive limit. DAC 2—If true, DAC output is at the positive limit. If false, the DAC output is below the positive limit. DAC 3—If true, DAC output is at the positive limit. If false, the DAC output is below the positive limit. DAC 4—If true, DAC output is at the positive limit. If false, the DAC output is below the positive limit. DAC 5—If true, DAC output is at the positive limit. If false, the DAC output is below the positive limit. DAC 6—If true, DAC output is at the positive limit. If false, the DAC output is below the positive limit. DAC 7—If true, DAC output is at the positive limit. If false, the DAC output is below the positive limit. DAC 8—If true, DAC output is at the positive limit. If false, the DAC output is below the positive limit.
	Bd ID Out is provided for flow control. You can string together NI-Motion VIs by wiring the Bd ID Out terminal of one VI to the Board ID terminal of the next VI.
	error out contains error information. If error in indicates an error, error out contains the same error information. Otherwise, it describes the error status that this VI produces. status is TRUE if an error occurred, or FALSE if not. If status is TRUE, code is a nonzero error code. If status is FALSE, code is zero or a warning code. code is a number identifying an error or warning. If status is TRUE, code is a nonzero error code. If status is FALSE, code is zero or a warning code. Use the error handler VIs to look up the meaning of this code and display the corresponding error message. source is a string that indicates the origin of the error, if any. Typically, source is the name of the VI in which the error occurred.

Using This VI

The Read DAC Limit Status VI returns the positive and negative torque limit status of the DAC output. Independent DACs that are not mapped to axes do not have torque limits, so those DACs will always return False.

A DAC torque limit status is True (1) when the DAC output is saturated at the corresponding limit. This information tells you that the motor is operating at its maximum torque, probably due to an excessively high value of acceleration or deceleration. It also can indicate excessive friction on the axis, a completely stalled motor, or some other system fault.

When an axis is active (not in the killed, motor off state), this VI returns the instantaneous state of the torque limit circuits. If the axis trips out on following error (a typical occurrence when operating at the torque limits), the DAC limit status is latched so you can tell which limit, positive or negative, caused the following error trip. The status remains latched until the axis is activated again by a Start, Stop, or Blend Motion VI.