2 batching examples, 1 example 1, Example 1 – Rice Lake 320IS Plus Intrinsically Safe Digital Weight Indicator - Installation Manual User Manual
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320IS Plus Installation Manual
7.2
Batching Examples
This section contains two examples of batching routines using setpoints to change the state of a digital output
controlling the external equipment.
7.2.1
Example 1
The following example uses seven setpoints to dispense material from a hopper in 100
LB
batches and to
automatically refill the hopper when its weight drops below 300
LB
.
Digital inputs 1 and 2 are assigned to batch start and batch run functions: BATRUN must be on (low) before the
BATSTA input starts the batch.
DIGIN1=BATSTA
DIGIN2=BATRUN
BATCHNG=MANUAL
Setpoint 1 ensures that the hopper has enough material to start the batch. If the hopper weight is 300
LB
or
higher, setpoint 1 is tripped.
SETPOINT=1
KIND=GROSSSP
VALUE=300
TRIP=HIGHER
BATCH=ON
ALARM=ON
Setpoint 2 waits for standstill, then performs a tare to put the indicator into net mode.
SETPOINT=2
KIND=WAITSS
PSHTARE=ON
Setpoint 3 is used as a reference (relative setpoint) for setpoint 4.
SETPOINT=3
KIND=NETSP
VALUE=0
TRIP=HIGHER
BATCH=OFF
TIMER
Tracks the progress of a batch sequence based on a timer.
The timer value, specified in tenths of a second on the VALUE parameter,
determines the length of time allowed between start and end setpoints. The
indicator START and END parameters are used to specify the start and end
setpoints. If the END setpoint is not reached before the timer expires, the digital
output associated with this setpoint is activated.
CONCUR
Allows a digital output to remain active over a specified portion of the batch
sequence. Two types of concur setpoints can be configured:
Type 1 (VALUE=0):
The digital output associated with this setpoint becomes
active when the START setpoint becomes the current batch step and remains
active until the END setpoint becomes the current batch step.
Type 2 (VALUE > 0):
If a non-zero value is specified for the VALUE parameter, that
value represents the timer, in tenths of a second, for this setpoint. The digital
output associated with this setpoint becomes active when the START setpoint
becomes the current batch step and remains active until the timer expires.
If more than one concurrent setpoint is configured, each must
be assigned to a different digital output.
Kind
Description
Batch
Continuous
Table 7-1. Setpoint Kinds (Continued)
Note