Motion Axis Shutdown (MASD)
This information applies to the
CompactLogix
5370, ControlLogix
5570, Compact GuardLogix
5370, GuardLogix
5570, Compact GuardLogix
5380, CompactLogix
5380, CompactLogix
5480, ControlLogix
5580, and GuardLogix
5580 controllers. Controller differences are noted where applicable.Use the Motion Axis Shutdown (MASD) instruction to force a specified axis into the Shutdown state. The Shutdown state of an axis is the condition where the drive output is disabled, servo loop deactivated, and any available or associated OK solid-state relay contacts open. The axis remains in the Shutdown state until either an Axis or Group Shutdown Reset is executed.
Architecture | Standard | Safety |
---|---|---|
CompactLogix 5370, ControlLogix 5570, Compact GuardLogix 5370, and GuardLogix 5570 controllers | Yes | No |
Compact GuardLogix 5380, CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, and GuardLogix 5580 controllers | Yes | No |
Available Languages
Ladder Diagram
Function Block
This instruction is not available in function block.
Structured Text
MASD(Axis,MotionControl);
Operands
Ladder Diagram and Structured Text
Operand | Type CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, Compact GuardLogix 5380, and GuardLogix 5580 controllers | Type CompactLogix 5370, ControlLogix 5570, Compact GuardLogix 5370, and GuardLogix 5570 controllers | Format | Description |
---|---|---|---|---|
Axis | AXIS_CIP_DRIVE AXIS_VIRTUAL | AXIS_CIP_DRIVE AXIS_GENERIC AXIS_GENERIC_DRIVE AXIS_SERVO AXIS_SERVO_DRIVE AXIS_VIRTUAL Tip: AXIS_GENERIC is supported by the ControlLogix 5570 and the GuardLogix 5570 controllers only. | Tag | Name of the axis on which to perform operation. For controllers that support the REF_TO motion data types, the supported axis operand type can be replaced by an equivalent REF_TO type. |
Motion | MOTION_INSTRUCTION | Structure used to access instruction status parameters. |
See
Structured Text Syntax
for more information on the syntax of expressions within structured text. MOTION_INSTRUCTION Structure
Mnemonic | Description |
---|---|
.EN (Enable) Bit 31 | It is set when the rung makes a false-to-true transition and remains set until the servo message transaction is completed and the rung goes false. |
.DN (Done) Bit 29 | It is set when the axes have been successfully set to Shutdown state. |
.ER (Done) Bit 28 | It is set to indicate that the instruction detected an error, such as if you specified an unconfigured axis. |
Description
The MASD instruction directly and immediately disables drive output, disables the servo loop, and opens any associated OK contacts. This action places the axis into the Shutdown state.
Another action initiated by the MASD instruction is the clearing of all motion processes in progress and the clearing of all the motion status bits. Associated with this action, the command also clears all motion instruction IP bits that are currently set for the targeted axis.
The MASD instruction forces the targeted axis into the Shutdown state. One of the unique characteristics of the Shutdown state is that, when available, the OK solid state relay contact for the motion module or drive is Open. Where available this feature can be used to open up the E-Stop string that controls main power to the drive system. Note that there is typically only one OK contact per motion module which means that execution of an MASD instruction for either axis associated with a given module opens the OK contact.
Another characteristic of the Shutdown state is that any instruction that initiates axis motion is blocked from execution. Attempts to do so result in an execution error. Only by executing one of the Shutdown Reset instructions can motion be successfully initiated.
The axis remains in the shutdown state until a Motion Axis Shutdown Reset (MASR), a Motion Group Shutdown Reset (MGSR), or a Motion Coordinate Shutdown Reset (MCSR) instruction executes. If the axis is associated with a Coordinate System, the axis will be reset if the Motion Coordinate Shutdown Reset (MCSR) instruction executes.
IMPORTANT:
The instruction execution may take multiple scans to execute because it requires multiple coarse updates to complete the request. The Done (.DN) bit is not set immediately, but only after the request is completed.
Additionally, for CIP motion, the MASD instruction supports canceling the Motion Drive Start (MDS) instruction. This includes clearing the MDS In Process (.IP) bit, and clearing the DirectVelocityControlStatus and the DirectTorqueControlStatus bit in the Motion Status attribute.
In this transitional instruction, the relay ladder, toggle the Rung-condition-in from cleared to set each time the instruction should execute.
Master Driven Speed Control (MDSC) and the MASD Instruction
When the axis is shut down:
- The IP bit of the Master Driven Axis Control (MDAC) instruction is reset on an axis that is shutdown.
- The AC bit of the MDAC instruction is reset when the axis is stopped as it is shutdown.
- The MASD instruction clears the pending Master Axis for all future single motion instructions.
Affects Math Status Flags
No
Major/Minor Faults
None specific to this instruction. A major fault can occur if an uninitialized reference or a reference of the incorrect type is passed to the Axis operand. See
Common Attributes
for operand-related faults. Execution
Ladder Diagram
Condition/State | Action Taken |
---|---|
Prescan | The .EN, .DN, and .ER are cleared to false. |
Rung-condition-in is false | The .EN bit is cleared to false if the .DN or .ER bit is true. |
Rung-condition-in is true | The .EN bit is set to true and the instruction executes. If the EN bit is set to false, then there is no action taken. |
Postscan | N/A |
Structured Text
Condition/State | Action Taken |
---|---|
Prescan | See Prescan in the Ladder Diagram table |
Normal execution | See Rung-condition-in is false, followed by rung is true in the Ladder Diagram table. |
Postscan | See Postscan in the Ladder Diagram table. |
Error Codes
See
Motion Error Codes (.ERR)
for Motion Instructions.Extended Error Codes
Extended Error Codes provide additional instruction-specific information for the error codes that are generic to many instructions. See
Motion Error Codes (.ERR)
for Motion Instructions.MASD Changes to Single Axis Status Bits
Axis Status Bits
Bit Name | State | Meaning |
---|---|---|
ServoActionStatus | FALSE | The axis is in the Servo Off state with the servo loop inactive. |
DriveEnableStatus | FALSE | The drive enable output is inactive. |
ShutdownStatus | TRUE | The axis is in the shutdown state. |
Motion Status Bits
Bit Name | State | Meaning |
---|---|---|
AccelStatus | FALSE | Axis is not Accelerating. |
DecelStatus | FALSE | Axis is not Decelerating. |
MoveStatus | FALSE | Axis is not Moving. |
JogStatus | FALSE | Axis is not Jogging. |
GearingStatus | FALSE | Axis is not Gearing. |
HomingStatus | FALSE | Axis is not Homing. |
StoppingStatus | FALSE | Axis is not Stopping. |
PositionCamStatus | FALSE | Axis is not Position Camming. |
TimeCamStatus | FALSE | Axis is not Time Camming. |
PositionCamPendingStatus | FALSE | Axis does not have a Position Cam Pending. |
TimeCamPendingStatus | FALSE | Axis does not have a Time Cam Pending. |
GearingLockStatus | FALSE | Axis is not in a Gear Locked condition. |
PositionCamLockStatus | FALSE | Axis is not in a Cam Locked condition. |
DirectVelocityControlStatus | FALSE | Axis is not under Direct Velocity Control. |
DirectTorqueControlStatus | FALSE | Axis is not under Direct Torque Control. |
Examples
Ladder Diagram
Structured Text
MASD(myAxis, myMotionControl);
Relay Ladder
Structured Text
MASD(myAxis, myMotionControl);
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