Precision Digital Corporation PD6622-L2N, Инструкция по эксплуатации

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Loop Leader PD6620 Series Loop-Powered Flow Rate/Totalizers Instruction Manual
38
Meter Operation
The meter can accept a 4-20 mA current signal and
display it in engineering units from -9999 to 99999 on
the top line and the total from 0 to 99,999,999 (with
commas, if desired) on the bottom line.
For example, a 4-20 mA signal could be displayed as
-50.00 to 50.00 on the top line.
The dual-line display can be customized to display the
process variable and other parameters in a wide vari-
ety of ways. Typically, the top line is used for the flow
rate while the bottom line is used for total, grand total,
engineering units, custom tag, or process variable
percentage of full scale.
If the total is disabled, the 4-20 mA input can be
scaled to display the process in two different scales;
for example: with PV2 enabled, the top display could
indicate level in feet and the bottom display could indi-
cate the volume in gallons.
Front Panel Buttons Operation
Button Symbol Description
Press to enter or exit
Programming Mode
, view
settings, or exit max/min
readings
Press to display max/min
readings or other
parameter/function
assigned through the
User
menu
Press to reset max/min
readings or other
parameter/function
assigned through the
User menu
Press to acknowledge
alarms or other
parameters/function
assigned through the
User
menu
Function Keys Operation
During operation, the programmable function keys op-
erate according to the way they have been pro-
grammed in the
Advanced Features – User
menu.
The table above shows the factory default settings for
F1, F2, and F3.
A hint message may be enabled to provide a descrip-
tion of what each function key does prior to executing
their assigned function. See
Enabling the Function
Key Hint Feature (
HINT
) on page 36 .
Digital Input Operation
A digital input is standard on the meter. This digital
input is programmed identically to function keys F1,
F2, and F3. The input is triggered with a contact
closure between DI+ and DI-, or with an active low
signal. During operation, the digital input operates
according to the way it has been programmed in the
Advanced Features – User
menu.
Maximum/Minimum Readings
The max & min readings (peak & valley) reached by
the process can be displayed either continuously or
momentarily.
Display momentarily by pressing the F1 key (default)
or assigning to any of the other function keys or to the
digital input in the
User
menu.
Display continuously by pressing the
Enter
button
while the max/min is being displayed to lock the dis-
play. Press
Enter
again to unlock.
Any of the F1-F3 function keys (buttons) and the digi-
tal input can be programmed to reset the max & min
readings. The meters are set at the factory to display
the max reading by pressing the Right Arrow/F1 but-
ton and to use the Up-Arrow/F2 button to access the
Reset
menu. Press the
Right Arrow
button to cycle
through the available parameters to reset.
Top Line: Process Value
Bottom Line: Max & Min