Rice Lake 880 Performance Series Indicator/Controller Technical/Service Manual - Manual (Page 87)

Setpoints 81
8.0 Setpoints
The 880 indicator provides 20 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 to control external equipment functions, or to make conditional
decisions.
Note
See Section 3.2.13 on page 49 for setpoint menu layout.
Weight-based setpoints are tripped by values specified in primary units only.
8.1 Batch and Continuous Setpoints
880 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 880 can use setpoints to control up to 20
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, the BATCHG parameter on the SETPTS menu must be set to auto or manual. AUTO
sequences repeat continuously after receiving a single initial BATSTR signal. MANUAL sequences require a
BATSTR signal each time a single batch is run. The BATSTR signal can be initiated by a digital input, serial
command. Set the BATCHG parameter to OFF to disable batch setpoints.
For setpoint kinds that can be used as either continuous or batch setpoints, the BATSEQ parameter must also
be set ON. (Setpoint kinds that can only be used as batch setpoints do not require the BATSEQ parameter.) If
the setpoint is defined but the BATSEQ 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
%REL Percent relative setpoint. Performs functions based on a specified percentage
of the target value of a referenced setpoint, using the same weight mode as the
referenced setpoint. The actual target value of the %REL setpoint is calculated
as a percentage of the target value of the referenced setpoint. X X
PAUSE Pauses the batch sequence indefinitely. A BATSTR signal must be initiated to
continue the batch process. X
DELAY Delays the batch sequence for a specified time. The length of the delay (in
tenths of a second) is specified by the VALUE parameter. X
Table 8-1. Setpoint Kinds