Page 72 Foundation Fieldbus RMA803 Remote Indicator User's Guide Revision 4
Integration of Inputs
There are three internal registers used for the totalization:
• Total = The net increment is added every cycle, irrespective of the status.
• Atotal = The absolute value of the net increment is added every cycle, irrespective of status.
• Rtotal = The absolute value of the net increments with status as Bad (rejects) are added to this
register.
The most significant part of Total can be read in the output OUT, and of Rtotal in RTOTAL.
OUT_RANGE is used only for display of the totals by a host. The high and low range values of
OUT_RANGE have no effect on the block.
Types of Integration
The value of OUT can start from zero and go up or it can start from a Setpoint value (TOTAL_SP)
and go down. The Reset option can be automatic, periodic, or on demand. This is defined by the
enumerated parameter INTEG_TYPE:
• UP_AUTO – It counts up with automatic reset when TOTAL_SP is reached
• UP_DEM – It counts up with demand reset, and the block resets only when the operator resets
the block.
• DN_AUTO – The block is reset when the output becomes zero. The integration starts as SP and
increments are subtracted from the SP.
• DN_DEM – The output is calculated even beyond zero till the block is reset. The integration
starts from SP.
• PERIODIC – The integration is done for the assigned period (specified in seconds in
CLOCK_PER). After that period, the block is reset automatically.
• DEMAND – The integration is done (positive or negative depending on the direction of the
flow) until the block is reset.
• PER&DEM – It is a combination of periodic and demand types. The integration is carried till
the end of the specified period and after that period is automatically reset. The block can be
reset at any time, before the end of periodic data set.
The first four types indicate use as a batch totalizer with a setpoint TOTAL_SP. The count does not
stop at TOTAL_SP going up or zero going down, as it is important to get the True total of flow.
Two outputs, OUT_TRIP and OUT_PTRIP, are associated with the four types. The next three
types indicate that TOTAL_SP and the trip outputs are not used. The Periodic type (5) disables reset
action based on RESET_IN, but has no impact on OP_CMD_INT.
The internal registers always add the net increments. Counting down is done by setting OUT to the
value of TOTAL_SP minus the most significant part of Total.
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