PD6928 Ex-Proof & I.S. Loop-Powered Flow Rate/Totalizer
Instruction Manual
72
Batch Controller Operation
Selecting batch control for relay 1 enables the
batching features on the meter. The top display is
changed to show the total and the bottom display is
changed to display the preset batch amount. The
function keys are changed so that F1 starts a batch,
F2 opens the preset menu to allow the preset value to
be changed, and F3 stops the currently running batch.
Enabling batch control for relay 1 allows access to the
batch menu under relay 2 (this menu does not appear
by default). Refer to page
batch controller features.
The PD6928 has two open collector outputs that can
used for alarm indication. A 4-20 mA output option is
also available for retransmitting the process variable.
Default Batch Control Operation
The following describes the operation of the three
operating keys as programmed with default settings.
The digital input can be used to start and stop the
batch using a momentary pushbutton. See examples
for
START Key (F1)
Press the START button to begin a new batch
process. Press the START button to resume a batch
that has been stopped.
BATCH Key (F2)
Press the Batch button to access the Preset (batch
amount) menu. Program the batch with the arrow
keys and confirm with the Enter key.
STOP Key (F3)
Press the STOP key once during a batch to pause.
Press the STOP key while paused to stop and cancel
the batch.
•
Only the STOP Key is Enabled when a Batch
is Running.
During a batch process, only the
pause/stop functions are operational, other
keys are deactivated.
Batch Control Operation
Example
The following example shows how two-stage manual
batch control functions with a PD6928. This setup will
establish a 55-gallon preset for the batch, with a main
valve (high flow) that will close at 50 gallons, and a
trickle valve (low or restricted flow) that will close at
55 gallons. Because the first batch overruns by 0.10,
the batch preset will be changed to 54.90 for the next
batch to compensate for overrun.
Two-Stage Manual Batch Control
Setup Using Relays 1 & 2
The following table shows the parameters as they
appear within the
OUT RELAY
menu.
Parameter
Setting
Function
RELAY
OUTPUT 1
RLY 1
BATCH
Press Enter to assign relay
1 batch parameters.
BATCH
COUNT
UP
or
DOWN
Setup batch to count up
or down.
BATCH
MAXIMUM
100.00
GAL
This setting prevents the
operator from entering a
preset value that exceeds
a safety limit for the batch
process.
BATCH
MODE
MANUAL
AUTO
Press Enter to select
manual or automatic batch
control.
BATCH
PRESET
55.00 GAL
Enter the batch size.
BATCH
DELAY
ON
&
OFF
Enter the On & Off time
delays for relay 1,
if desired.
RELAY
OUTPUT 2
RLY 2
BATCH
Press Enter to assign relay
2 batch parameters.
BATCH
PRECLOSE
YES
PRECLOSE
5.00
Set the pre-close value to
5 to close the valve being
controlled by relay 2 so it
closes five gallons before
reaching the preset.
BATCH
DELAY
ON
&
OFF
Enter the On & Off time
delays for relay 2,
if desired.
RELAY
MESSAGE
MSG
RELAY 1
Enter a message to be
displayed while relay 1 is
on, if desired.
MSG
RELAY 2
Enter a message to be
displayed while relay 2 is
on, if desired.
If only one-stage batch control is desired, do not
assign relay 2 to batch. The following pages show
illustrations of how the above settings control the
batch operation. The display assignment shown is the
default.
