Watlow 12LS Controller User Manual

Page 69

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¦ PARAMETERS SPECIFIC TO EACH SEGMENT ¦
|-------------------------------------------------------------¦
¦ Setpoint ¦ Specifies setpoint to be reached at the ¦
¦ ¦ end of the segment. If the setpoint from¦
¦ ¦ the previous segment is the same, this ¦
¦ ¦ setpoint will be held during the segment¦
¦ ¦ (soak). If the setpoint is different ¦
¦ ¦ the setpoint will make a linear change ¦
¦ ¦ between the two setpoints over the time ¦
¦ ¦ of the segment (ramp). ¦
|-------------------¦-----------------------------------------¦
¦ Time ¦ Segment duration time. Time units are ¦
¦ ¦ selected from the GLOBALS menu. ¦
|-------------------¦-----------------------------------------¦
¦ Triggers ¦ Two logic inputs sensed during profile ¦
¦ ¦ segment execution. There are 2 types, ¦
¦ ¦ latched and unlatched. The state may be ¦
¦ ¦ ON or OFF. Default value is OFF ¦
|-------------------¦-----------------------------------------¦
¦ Event States ¦ The outputs of up to four events to be ¦
¦ ¦ set to the selected ON or OFF state at ¦
¦ ¦ the end of the segment. The default is ¦
¦ ¦ for all events to be OFF. ¦
|-------------------------------------------------------------|

Triggers: Triggers are logic inputs sensed during profile execution. There are two types, latched
and unlatched. Latched triggers must be TRUE for a segment to begin execution. Once sensed,
these triggers are never tested again. Unlatched triggers, however, are tested throughout the
execution of a segment. If an unlatched trigger goes FALSE while a segment is executing, the
control loop will go into WAIT mode with the segment timer stopped.

Each segment may have up to two triggers specified. Either one being TRUE, whether latched or
unlatched, is sufficient for a segment to begin executing.

Events: An event takes place at the end of a segment. Each segment may have up to four events
assigned. These events can be assigned to a specific logic output. They can be active ON or OFF.

Tolerance Hold ["Guaranteed Soak"]: A tolerance can be assigned to each segment of each
profile. This tolerance is a deviation from setpoint. If the process variable is beyond the tolerance
limit from the (instantaneous) setpoint, then the segment will enter a tolerance hold until the
process variable is within tolerance. There is no logic output available to indicate the tolerance
hold condition, only a visual indication.

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