Error Bits Register

If the axis is in closed loop position control, this bit is set when the Position Error exceeds the Position Error Tolerance parameter.

If the axis is in closed loop velocity control, this bit is set when the Velocity Error exceeds the Velocity Error Tolerance parameter.

This error is not used in I-PD control.

If the Control Output exceeds the Output Limit parameter (positive or negative), then the Control Output is saturated and this bit is set. This bit is not set when the Control Output is limited at the DAC output stage. It is just silently truncated. Truncation at this stage results from applying the Output Bias and/or Output Polarity.

This bit is set when the Fault Input for the axis goes active. This bit does latch unlike the Fault Input State status bit.

Some axes do not have a Fault Input.

This bit is set when the Positive Limit Input becomes active. Do not confuse this with the Positive Overtravel bit.

This bit is set when the Negative Limit Input becomes active. Do not confuse this with the Positive Overtravel bit.

This bit is set when the RMC detects that no transducer is connected. The following list indicates when this occurs for each transducer type.

Analog Voltage	RMC75/150: This bit will not turn on for voltage feedback. The Transducer Overflow bit is used instead. RMC200: A broken wire is detected, as indicated by: The voltage input is less than the minimum differential voltage (-10.5 V for the A8 and -10.2 V for the U14), and One of both of the individual input signals (In+ and In-) are out of range (see A8 or U14 specifications).
Analog Current	RMC75/150: The current is less than 3.6mA. RMC200: A broken wire is detected, as indicated by the current being less than the Analog Underflow Limit (default is 3.6mA).
MDT	RMC75 or RMC200: The RMC does not detect a start pulse (for Start/Stop) or rising edge on the Return pulse (for PWM). RMC150: The RMC has not detected a start pulse (for Start/Stop) or rising edge on the Return pulse (for PWM) for the last six (6) control loops.
Load Cell	LC8: The RMC does not detect valid data. This may be due to an internal Out of Range Error, Data not Valid, or Analog to Digital Converter not Initialized error, which are all reported in the Transducer Status B register.
Quadrature	RMC75: A broken A or B wire is detected, as indicated by the A Wire Break and B Wire Break status bits. RMC150: This bit is not used by the RMC150. RMC200: A broken A or B wire is detected, as indicated by the A Wire Break and B Wire Break status bits.
Resolver	The RMC detects an over-speed, over-acceleration, or voltage error on the Resolver.
SSI	The RMC does not detect any valid data. The data line is the wrong polarity at either the beginning of the serial data stream or the end of the serial data stream, indicating the line is not being actively driven by the transducer.

 

In general (see the Input Estimated status bit for details and exceptions, including the RMC150 MDT module), the No Transducer error bit is not set until the error condition is present for three consecutive loop times. When a No Transducer error condition is first detected, the RMC estimates the position by extrapolating the last two positions. The Input Estimated Status bit be will be on while this occurs. After the condition is detected 3 times in a row, the No Transducer error bit is set. The Input Estimated bit is always set while the error condition is active, even after the No Transducer error bit is set following the first 3 loop times.

Once the No Transducer error bit has been set, it cannot be cleared until a transducer is detected three loop times in a row.

 

This bit is set when the RMC detects an overflow on the input from the transducer. The following list indicates when this occurs for each transducer type.

Analog Voltage	RMC75: The voltage is greater than +10.1V or less than -10.1V. RMC150 (±5V Range): The voltage is greater than +5.04V or less than -5.04V. RMC150 (±10V Range: The voltage is greater than +10.08V or less than -10.08V. RMC200: An input signal is detected (that is, the No Transducer error is not set) but is not valid, as indicated by: The voltage is above the Analog Overflow Limit (default is 10.1 V), or The voltage is above the maximum differential voltage (10.5 V for the A8 and 10.2 V for the U14), or The voltage is below the Analog Underflow Limit (default is -10.1 V), or The voltage is below the minimum differential voltage (-10.5 V for the A8 and -10.2 V for the U14), or One of both of the individual input signals (In+ and In-) are out of range (see A8 or U14 specifications).
Analog Current	RMC75: The current exceeds 21mA. RMC150: The current exceeds 20.1mA. RMC200: An input signal is detected (that is, the No Transducer error is not set) but is not valid, as indicated by: The current exceeds the Analog Overflow Limit (default is 21.0 mA), or One of both of the individual input signals (In+ and In-) are out of range (see A8 or U14 specifications).
MDT	RMC75 or RMC200: The RMC does not detect a stop pulse (for Start/Stop) or falling edge on the Return pulse (for PWM) by the end of the control loop. RMC150: The RMC has not detected a stop pulse (for Start/Stop) or falling edge on the Return pulse (for PWM) after three (3) control loops.
Load Cell	LC8: The Millivolts/Volt value is greater than the Load Cell Overflow Limit or less than the Load Cell Underflow Limit, or the Millivolt Input is greater than 34.5 mV or less than -34.5 mV.
Quadrature	Not used for Quadrature.
Resolver	Not used for resolvers.
SSI	As specified by the SSI Overflow Mode.

 

In general (see the Input Estimated status bit for details and exceptions), the Transducer Overflow error bit is not set until the error condition is present for three consecutive loop times. When a Transducer Overflow error condition is first detected, the RMC estimates the position by extrapolating the last two positions. The Input Estimated status bit be will be on while this occurs. After the condition is detected 3 times in a row, the Transducer Overflow error bit is set. The Input Estimated bit is always set while the error condition is active, even after the Transducer Overflow error bit is set following the first 3 loop times.

Note:
The Noise Error bit may turn on because the Noise Error Rate parameter is set too low. The Noise Error Rate should be set to a value much higher than the expected velocity of the axis. If your axis is experiencing Noise Errors, this is the first item you should check. Setting the Noise Error Auto Stop to Status Only to avoid halting due to an overly low Noise Error Rate parameter can cause significant control problems.

 

This bit is set when the RMC detects transducer noise on the feedback, before it is filtered. The following list indicates when this occurs for various transducer types.

Position: Analog, MDT, SSI, Resolver	If the input rate of change of the input exceeds the rate specified by the Noise Error Rate parameter for a period of 3 loop times, then this error bit will be set. During noise less than 3 loop times, the Actual Position is estimated to allow recovery from electrical noise, during which time the Input Estimated Status bit will be on.   Make sure that  the Noise Error Rate parameter is set much higher than the expected velocity of the system. If it is set too low, the Actual Position and Actual Velocity may be incorrectly calculated, adversely affecting control.   A Noise Error can also be triggered on a Resolver axis if the speeds or accelerations exceed the maximums. See the Resolver Module specifications for details.
Position: Quadrature	If the RMC detects an illegal transition (both A and B signals transition simultaneously), or an overspeed condition (pulse frequency exceeds maximum specifications), for a period of 3 loop times, then the Noise Error bit will be set. During noise less than 3 loop times, the Actual Position is estimated, during which time the Input Estimated Status bit will be on.
Velocity: Analog	If the input rate of change of the input exceeds the rate specified by the Noise Error Rate parameter, then this error bit will be set. There is no 3 loop delay.
Pressure, Force, Load Cell: Analog and mV/V	If the input rate of change of the input exceeds the rate specified by the Noise Error Rate parameter, then this error bit will be set. There is no 3 loop delay.

This bit is set when the Target Position travels beyond the Positive Travel Limit and is not in the Direct Output state. The Target Position can exceed the Positive Travel Limit by up to half a transducer count before this error is triggered.

 

Note:
This bit turns on only when exceeding the limit or attempting to go further past the limit. It will turn off if a command is issued that keeps the axis in the same place or moves it toward the limit.

This bit is set when the Target Position travels beyond the Negative Travel Limit and is not in the Direct Output state. The Target Position can exceed the Negative Travel Limit by up to half a transducer count before this error is triggered.

 

Note:
This bit turns on only when exceeding the limit or attempting to go further past the limit. It will turn off if a command is issued that keeps the axis in the same place or moves it toward the limit.

When an invalid command or command with invalid parameters is issued, this bit is set and an error number is stored in the Last Error Number status register. Depending on the Event Log filter settings, this error may also be logged to the Event Log. See the Error Codes topic for a list of errors that cause this bit to be set. This bit is cleared when any valid command is issued.

This bit is set when a command has been modified. If a command contains an invalid Command Parameter, it may be modified. A command that has been modified will then be a valid command. For example, it the Requested Position is beyond the travel limits, the command will be automatically changed so that it will move to the limit. By default, an axis will halt when a command is modified. If the Command Modified Autostop is set to Status Only, then the axis will not halt and the modified command will be processed as usual.

When this error occurs, an error number will be stored in the Last Error Number status register. Depending on the Event Log filter settings, this error may also be logged to the Event Log. See the Error Codes topic for a list of errors that cause this bit to be set. This bit is cleared when any valid command is issued.

When an attempt is made to write an invalid value to a parameter, this bit is set and an error number is stored in the Last Error Number status register. Depending on the Event Log filter settings, this error may also be logged to the Event Log. See the Error Codes topic for a list of errors that cause this bit to be set. This bit is cleared when any valid parameter write occurs.

When an unexpected condition occurs that does not have its own error bit, this bit is set and an error number is stored in the Last Error Number status register. Depending on the Event Log filter settings, this error may also be logged to the Event Log. See the Error Codes topic for a list of errors that cause this bit to be set.

Applies to axis with a Control Output assigned to the RMC200 CA4, CV8, or U14 modules.

Indicates that physical fault occurred on the output such as an overcurrent or overvoltage. This may be caused by an open wire or shorted wire. Once the cause is remedied, the output will likely function properly.

This error bit is set in the same way that the No Transducer error bit is set, except this bit is set based on the secondary analog pressure/force input.

This error bit is set in the same way that the Transducer Overflow error bit is set, except this bit is set based on the secondary analog pressure/force input.

Note:
The Pressure/Force Noise Error bit may turn on because the Noise Error Rate parameter is set too low. The Pressure/Force Noise Error Rate should be set to a value much higher than the expected velocity of the axis. If your axis is experiencing Noise Errors, this is the first item you should check. Setting the Pressure/Force Noise Error Auto Stop to Status Only to avoid halting due to an overly low Noise Error Rate parameter can cause significant control problems.

 

This bit is set when the RMC detects transducer noise. If the input rate of change of the pressure or force input exceeds the rate specified by the Noise Error Rate parameter, then this error bit will be set.

This bit applies to the secondary analog pressure/force input. On pressure-only or force-only axes, the primary Noise Error bit #8 will apply to the pressure or force input.

In pressure/force control, this error bit is set when the Pressure/Force Error exceeds the Pressure/Force Error Tolerance.

In pressure/force limit, this bit is set as follows:

• Positive Mode:
  When the Actual Pressure/Force exceeds the Target Pressure/Force by more than the Pressure/Force Error Tolerance
  (Actual > Target + Error Tolerance).
  

• Negative Mode:
  When the Actual Pressure/Force is less than the negated Target Pressure/Force by more than the Pressure/Force Error Tolerance
  (Actual < -Target - Error Tolerance).

• Bidirectional Mode:
  When either of the Positive or Negative cases are true.