YOKOGAWA 800 plus, Инструкция по эксплуатации

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In batch control mode with “external gate”, the meter waits a the end of every cycle
until an external gate input is grounded for a minimum of 3.33 ms. This starts a new fill
cycle by energizing Relay #1 and resetting the Batch Total.
Gate time is not used.
Three values are tracked and can be separately displayed by pressing the RESET key: Item
#1, the Batch Total; Item #2, the Grand Total of all batches or Number of Batches (select-
able during setup); and Item #3, the Fill Rate.
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Item #1, Batch Total, is the total of input pulses for that batch. It may be configured to
count up from 0 to a preset, or to count down from a preset to 0. The preset value is
placed in
ALARM1 . SCALE1 is positive whether counting up or down.
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Item #2, Grand Total, is the sum of previous Batch Totals and the current Batch Total. It
can overflow to exponential format.
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Item #2 (alternate), Number of Batches, is the current count of batches. SCALE1 does
not apply. dECPt1 is set to 1.
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Item #3, Fill Rate, is calculated with a fixed 20 ms gate time . It may be displayed as Item
#3.
BATCH CONTROL WITH A 4-20 mA OUTPUT FLOW METER
Application: Fill 55 gallon tanks. Use a
4-20 mA flow meter where 4 mA = 0 and 20
mA = 39.20 GPM. Slow down filling at 54
gallons. Cycle batches automatically with 20
sec between cycles. Display batch total & fill
rate to 2 places. Also track number of
batches.
Solution: Use an Extended counter with
a dual relay output board. Set Input to “Rate
Batch.” Set Batch to count up to ALARM1, to
use Gate Time as delay between batches,
and to make Item #2 the number of batches.
Set Gate Time to 20 sec. Set DecPt1 and
DecPt 2 to two decimal places for Items #1
and #3 (Batch Total and Rate). Scale Item
#3 (Rate) using the coordinates of 2 points
method so that 20.0000 mA will be displayed
as 39.20 GPM. Scale Item #1 (Batch Total)
by entering a Scale1 of 1.66667 and a mul-
tiplier of 0.01. That is because totalizing
sums readings in gallons every second.
Since our rate is in GPM, we have to divide
by 60. Enter an Offset1 of 55.00to serve as
the batch setpoint in gallons. Set Setpoint2
to 54.00 to activate Relay 2 to slow the fill
rate.