MotoHawk:Blocks:Fault Definition

Fault Definition

This MotoHawk™ block defines a Fault, which can be viewed from MotoTune, and may have several user-defined Fault Actions associated with it.

Block ID

motohawk_fault_def

Library

MotoHawk_lib/Fault Management Blocks

Description

Faults are associated with the 'detection' of a fault condition. Define the 'Responses' to fault conditions using Fault Action blocks.

A fault has three Boolean states associated with it: Suspected, Active, and Occurred.

• Suspected: Suspected state indicates that some model logic has determined a fault condition. This is typically something like a signal out of range, or the comparison of conditions that should not normally occur together.
  
  
• Active: When the Suspected status is true for a number X out of Y counts (as user-defined), over a window of time, then the fault becomes Active. The fault will become Inactive again when the Suspected status is false for the full Y counts.
  
  
• Occurred: A fault has Occurred if it has ever transitioned from Active to Inactive.

Block Parameters

Parameter Field	Values	Comments/Description
Fault Name	Alpha-numeric text, single-quote enclosed	Specify Fault Name. No special characters, such as spaces, dashes, commas (underscore allowed).
Mode		Set Fault to one of several modes, which define the behavior
	Disabled	The suspected, active, and occurred states are all cleared, and the X/Y counts remain zero
	Enabled	When an active fault has a false suspected status false for Y counts, the fault becomes inactive, and its occurred status is set.
	Sticky	Once the fault becomes active, it never goes inactive. This means that the occurred status is never set. The suspected, active and occurred states are all cleared after a power cycle.
	Enabled - Persistent	Like Enabled, but remembers all state across a power-cycle. This includes any suspected, active, occurred state, and X/Y counts.
	Sticky - Persistent	Like Sticky, but remembers all state across a power-cycle. This includes any suspected, active, occurred state, and X/Y counts.
	Save Occurred	Like Enabled, but remembers the occurred status. Any active faults at power-down become occurred on power-up.
ID	"[]" bracketed value	Enter value to be used for fault ID
Faulty Sample (X)	Numeric	Number of faulty signal samples required per sample set(Total Sample (Y)) to declare 'Active' fault. Note: This requires a minimum of (X)/(block execution rate) units of time.
Total Sample (Y)	Numeric	Number of samples in which to gather X Fault Samples. Also, the number of non-Fault samples required to clear an 'Active' fault. Note: The time required for a single pass happens in (Y)/(block execution rate) units of time after signal clears.
Input Suspected Status	Check Box (enable)	The Suspected status of a fault is determined entirely by the model, and is usually input to this block directly. It can also be set via the MotoHawk Fault Set block. Checking "Input Suspected Status" will make this port available. Functionally, this adds the behavior of the "MotoHawk Fault Set" block to the definition block, for convenience.
Allow Indeterminate Input (values other than 0 or 1)	Check Box (enable)	Normally the Suspected input is a Boolean value, where 0 means "OK", and 1 means "Fault". Both X and Y counters increment whenever the Suspected status is 1, and only Y increments when the Suspected status is 0. When the checkbox "Allow Indeterminate Input (values other than 0 or 1)" is checked, then the Suspected input may be any value, of any data type. When the input is 0 or 1, it means "OK" or "Fault" as before. When the input is any other value, the Suspected status is not set, and, when "Update X/Y Values" is checked, the X/Y counters are not updated. This basically causes the fault detection logic to "pause", as though the block were placed into a disabled subsystem. Several other MotoHawk I/O blocks, such as the Spark Sequence and Digital Output, produce diagnostics which are equal to 0,1,or 2, which correspond to "OK", "Fault", or "Indeterminate" respectively. These can be directly connected to either a Fault Definition or Fault Set block with Indeterminate option checked.
Update (X/Y) Values	Check Box (enable)	Enable X/Y counter state update once every "Downsample Count" executions of the block. When unchecked, the Suspected status may still be updated, but X/Y counts do not increment. The X/Y state can also be updated using the Fault Set block with the "Update X/Y Values" parameter checked, or explicitly using the Fault Update block. Note that "Update X/Y Values" may still be used, even when "Input Suspected Status" is not checked. This simply means that the X/Y counters are advanced when this block executes with inherited sample time, using the current Suspected status as set from another Fault Set block.
Downsample Count	Numeric Value	Value used with X & Y update to set number of execution cycles per updates. For 0 or 1, no extra state and counter logic is added, and the X/Y states update every time the block runs.
Use uploaded Mode / X / Y values from MotoTune	Check Box (enable)	Check to use uploaded Mode / X / Y values from MotoTune
Use uploaded Fault Actions from MotoTune	Check Box (enable)	Check to use uploaded Fault Actions from MotoTune
Show Fault Action Routing	Check Box (enable)	Show Fault routing Assignment Fields. Map up to four Fault Actions per fault, defined by using the Fault Action blocks along with Action Conditions.
Action (1-4)	Alpha-numeric text, single-quote enclosed	Name the Action for identification/reference.
Action Condition (1-4)	Selectable from list - Suspected, etc.	Each of these four routings may use any combination of the Suspected, Active, or Occurred status of the fault. Responses to faults (Fault Actions) thus remain decoupled in the design from fault detection (Fault Definitions)