Owner's manual

7-5
Integrator (INT) Function Block
Specifying Rate Time Base The time unit parameters (TIME_UNIT1 and TIME_UNIT2) specify
the rate time base of the inputs (IN_1 and IN_2, respectively). The
block uses the following equations to compute the integration
increment:
The block supports the following options for TIME_UNIT1 and
TIME_UNIT2:
• For seconds, TIME_UNIT = 1
• For minutes, TIME_UNIT = 60
• For hours, TIME_UNIT = 3600
• For days, TIME_UNIT = 86400
Setting Reverse Flow at
the Inputs
Reverse flow is determined by either the sign of the value at IN_1 or
IN_2, or the discrete inputs REV_FLOW1 and REV_FLOW_2. When
the REV_FLOW input is True, the block interprets the associated IN
value as negative.
Calculating Net Flow Net flow is calculated by adding the increments calculated for each IN.
When ENABLE_IN2 is False, the increment value for IN_2 is
considered zero. When ENABLE_IN2 is True, the value of IN_2 is used
in the calculation.
To determine the net flow direction that is to be included in the
integration, configure the Flow Forward and Flow Reverse integration
options attribute (INTEG_OPTS). When Flow Forward is True, positive
increments are included. When Flow Reverse is True, negative
increments are included. When both Flow Forward and Flow Reverse
are True, positive and negative increments are included.
Integration Types The integration type attribute (INTEG_TYPE) defines the integrate up,
integrate down, and reset characteristics of the block. Choose from the
following options:
0 to SP - auto reset at SP – Integrates from zero to the setpoint (SP)
and automatically resets when the SP is reached.
0 to SP - demand reset – Integrates from zero to the SP and resets
when RESET_IN or the operator command to reset the integrator
(OP_CMT_INT) transitions to True (1).
SP to 0 - auto reset at SP – Integrates from the SP to zero and
automatically resets when zero is reached.
SP to 0 - demand reset – Integrates from the SP to zero and resets
when RESET_IN or OP_CMD_INT transitions to True.
0 to ? - periodic reset – Counts upward and resets periodically. The
period is set by the CLOCK_PER attribute.
x
IN_1
TIME_UNIT1
-----------------------------------=
y
IN_2
TIME_UNIT2
-----------------------------------=
Where
x: the converted IN_1 value (based on the options you configure)
y: the converted IN_2 value (based on the options you configure), or zero if you select not to
use a second input
OUT[t-1]: the value of OUT from the previous cycle