Rice Lake 920i USB Installation Manual V5.05 - Manual (Page 81)

Setpoints 75
9.0 Setpoints
The 920i indicator provides 100 configurable setpoints for control of both indicator and external equipment
functions. Setpoints can be configured to perform actions or functions based on specified parameter conditions.
Parameters associated with various setpoint kinds can, for example, be configured to perform functions (print, tare,
accumulate), to change the state of a digital output controlling indicator or external equipment functions, or to
make conditional decisions.
Note
Weight-based setpoints are tripped by values specified in primary units only.
9.1 Batch and Continuous Setpoints
920i setpoints can be either continuous or batch setpoints.
Continuous setpoints are free-running: the indicator constantly monitors the condition of free-running setpoints at
each A/D update. The specified setpoint action or function is performed when the designated setpoint
parameter conditions are met. A digital output or function assigned to a free-running setpoint continuously
changes state, becoming active or inactive, as defined by the setpoint parameters.
Batch setpoints are active one at a time, in an ordered sequence. The 920i can use setpoints to control up to 100
separate batch processing steps.
A digital output associated with a batch setpoint is active until the setpoint condition is met, then latched for
the remainder of the batch sequence.
To use batch setpoints, you must activate the BATCHNG parameter on the SETPTS menu. This parameter
defines whether a batch sequence is automatic or manual. AUTO sequences repeat continuously, while
MANUAL sequences require a BATSTRT signal. The BATSTRT signal can be initiated by a digital input,
serial command,
Batch Start softkey, or the StartBatch function in an iRite program.
For setpoint kinds that can be used as either continuous or batch setpoints, the BATCH parameter must also be
set ON. (Setpoint kinds that can only be used as batch setpoints do not require the BATCH parameter.) If the
setpoint is defined but the BATCH parameter is off, the setpoint operates as a continuous setpoint, even during
batch sequences.
Note
In applications that contain both batch setpoint routines and continuous setpoints, continuous setpoints
should be kept separate from the batch sequence. This is especially true when using CONCUR or TIMER
setpoints to perform actions or functions based on the batch sequence. CONCUR and TIMER setpoints should
not be included in the referenced START and END setpoint sequence.
Kind Description Batch Continuous
OFF Setpoint turned off/ignored.
GROSS Gross setpoint. Performs functions based on the gross weight. The target
weight entered is considered a positive gross weight. X X
NET Net setpoint. Performs functions based on the net weight. The target weight
entered is considered a positive net weight value. X X
–GROSS Negative gross weight. Performs functions based on the gross weight. The
target weight entered is considered a negative gross weight. X X
–NET Negative net weight. Performs functions based on the net weight. The target
weight entered is considered a negative net weight value. X X
ACCUM Accumulate setpoint. Compares the value of the setpoint to the source scale
accumulator. The accumulator setpoint is satisfied when the value of the source
scale accumulator meets the value and conditions of the accumulator setpoint. X X
ROC Rate-of-change setpoint. Performs functions based on the rate-of-change
(ROC) value. X X
+REL Positive relative setpoint. Performs functions based on a specified value above
a referenced setpoint, using the same weight mode as the referenced setpoint. X X
–REL Negative relative setpoint. Performs functions based on a specified value below
a referenced setpoint, using the same weight mode as the referenced setpoint. X X
Table 9-1. Setpoint Kinds