RotationalLoadSequencer provides lead-lag control of from 2 to 10 BooleanWritables based upon a fixed sequence. The number of active loads is determined by the Schedule and Required Loads inputs.
RotationalLoadSequencer is available in the HVAC folder of the vykonPro palette
Setup of the object involves the following properties, as follows:
Status
BStatus property which indicates the current status of the component.
Fault Cause
String property which indicates the current fault cause if any of the component.
Facets
Facets applied to the Out (A-J) slots.
Schedule
A StatusBoolean input that controls whether any control device should be on. If this input is true, at least one of the outputs will be active.
Load Failed
StatusBoolean property which indicates whether one of the commanded loads failed to start.
Number Outputs
Specifies the number of devices (outputs) that are controlled.
Required Loads
Specifies the number of devices (outputs) that should be active provided the Schedule input is true. This input can be linked to logic which evaluates the need for multiple loads to be energized such as in parallel pumping applications.
Rotate Mode
Enum property which determines the mode of operation. When set to interval, rotation occurs after the stations elapsed time exceeds the rotateInterval value, regardless of load runtime. When set to rotate, rotation occurs when the lead load's accumulated runtime (since being designated as the lead load) exceed the rotateInterval value. When set to manual, rotation occurs only when manually commanded.
Rotate Interval
Specifies the maximum amount of time that must elapse based on the rotate mode before the lead load is shifted automatically.
Feedback Delay Time
Specifies the delay time used to evaluate the feedback links (if any). If an active load does not indicate a running status via its feedback, then an additional load is started to maintain the number of running loads equal to the required number of loads.
Last Rotate Time
The timestamp of the last rotation of the lead load
Runtime Remaining Until Shift
The amount of runtime left until the lead load will be rotated, if the rotateMode is runtime.
Lead Load Enum
The load output which is designated as lead.
Lead Runtime At Start
The current accumulated runtime of the lead output recorded when the load is designated as lead.
Next Lead Load
The load output which is designated as lead.
Feedback A-J
A StatusBoolean input, to provide positive feedback that a controlled device actually started. If the feedback value does not show true within the Feedback Delay time, the output will show alarm, and the RotationalLoadSequencer switches to the next output. Setting this value to true (and not linking) disables this alarm feature.
Out A-J
StatusBoolean outputs, each typically linked to a BooleanWritable control point with a DiscreteTotalizerExt. Outputs are typically used to control loads of some type.
Runtime A-J
These are RelTime inputs that are used for runtime feedback for the corresponding Out A - J. These inputs will typically be linked to the ElapsedActiveTime property of the DiscreteTotalizerExt that is measuring the runtime of the corresponding Out A - J.
Disable Output
This action prompts the user to select which output to disable. This sets the selected output to false and disabled, effectively removing the load from the rotation. This action could be used to disable a load for maintenance or some other reason.
Enable Output
This action prompts the user to select which output to enable. This restores the selected output from being previously disabled.
Manual Command
This action prompts the user to select which output to command and whether to enable or disable the load. The action performs the same functionality as the "Disable Output" and "Enable Output" commands. The design is to allow linking control logic through a BooleanToSequencerCmd component.
Manual Rotate
This action forces the Rotational Load Sequencer component to rotate the lead load to the next available load in sequence.