Dwyer DPW - Manual (Page 13)

4.6.4 - Main Totalizer Reset Tabular Entry
The Main Totalizers reading can be reset by pressing ENTER button. A typical
display with flow meter Main Totalizer Reset screen is shown below.
The next conformation screen will appear only for 2 seconds.
If during these 2 seconds user will press ENTER button again, the Main Totalizer
volume will be reset to 0. Following screen will appear for 2 seconds.
4.7 - Submenu Pilot Totalizer
The total volume of the liquid is calculated by integrating the actual liquid flow rate
with respect to time. The Pilot Totalizer value is stored in the flow meter volatile
memory (SRAM) and saved every 100 ms. In case of power interruption the Pilot
Totalizer volume will be lost (reset to zero). The optional LCD/keypad and digital
communication interface commands are provided to:
- reset the totalizer to ZERO
- start the totalizer at a preset flow rate
- assign action at a preset total volume
- start/stop totalizing the flow
Note: Before enabling the Pilot Totalizer, ensure that all totalizer settings are
configured properly. Totalizer Start values have to be entered in % FS engineering
unit. The Totalizer will not totalize until the flow rate becomes equal to or more than
the Totalizer Start value. Totalizer Stop values must be entered in currently active
volume / mass based engineering units. If the Totalizer Stop at preset total volume
feature is not required, then set Totalizer Stop value to zero (default settings).
4.7.1 - Pilot Totalizer Mode Tabular Entry
This function determines whether Pilot Totalizer is Enabled or Disabled. The
following selections are available: Enabled or Disabled. The default entry is
Disabled.
The listed above Pilot totalizer Mode selections can be set with the Up and Dn
buttons and are accepted by pressing ENT button.
4.7.2 - Pilot Totalizer Flow Start Numerical Entry
The Pilot Totalizer Start Flow value can be entered in increments of 0.1% from 0.0
to 100.0% FS. A typical display with flow meter Pilot totalizer Start Flow settings is
shown below.
4.7.3 - Pilot Totalizer Event Volume Numerical Entry
Pilot Totalizer Event Volume value must be entered in currently active volume /
mass based engineering units. Totalizer action event become true when the
totalizer reading and preset "Event Volume" values are equal.
If the Totalizer Event at preset total volume feature is not required, then set Totalizer
Event Volume value to 0 (default settings). A typical display with flow meter Pilot
Totalizer Event Volume settings is shown below.
4.7.4 - Pilot Totalizer Reset Tabular Entry
The Pilot Totalizers reading can be reset by pressing ENTER button. A typical
display with flow meter Pilot Totalizer Reset screen is shown below.
The next confirmation screen will appear only for 2 seconds.
If during these two seconds user will press ENTER button again, the Pilot Totalizer
volume will be reset to 0. Following screen will appear for 2 seconds.
4.8 - Submenu Optical Outputs Numerical Entry
Two sets of optically isolated outputs are provided to actuate user supplied
equipment. These are programmable via digital interface or optional LCD/keypad
such that the outputs can be made to switch when a specified event occurs (e.g.
when a low or high flow alarm limit is exceeded or when the totalizer reaches a
specified value) or may be directly controlled by user.
The user can configure each optical output action from 11 different options:
- Disabled: No Action (output is not assigned to any events and not energized)
- Low Flow Alarm
- High Flow Alarm
- Range between H&L Flow alarm settings
- Main Totalizer reading exceed set limit
- Pilot Totalizer reading exceed set limit
- Low Temperature alarm (*RTD option only)
- High Temperature alarm (*RTD option only)
- Range between High and Low Temperature alarm (*RTD option only)
- Diagnostic: Output will be energized when any of the Diagnostic events are active
- Manual On Control: Output will be energized until Disabled option will be
selected.
A typical display with Optical Output Function selection is shown below.
The listed above Optical Output selections can be set with the Up and Dn buttons
and are accepted by pressing ENT button.
4.9 - Submenu Flow Meter Configuration
4.9.1 - Submenu Flow Meter Low Flow Cut–off Numerical Entry
The Low Flow Cut-off can be selected between 0.0 and 10.0 % of the FS range.
Flows less than the cut-off value are internally driven to zero and not totalized. The
analog 0 to 5 vdc or 4 to 20 mA current outputs are set to 0.0 Vdc and 4.00 mA
correspondently. The switching threshold for the low flow cut-off has 1.0% FS
hysteresis. A typical display with Low Flow Cut–off selection is shown below.
4.9.2 - Submenu Pulse Number Measure Interval Numerical Entry
Signal Processing software algorithm can be set to calculate flow rate based on two
different methods (see Section 4.9.4):
a) number of pulses over preset measure interval
b) pulse width measurement
Both methods calculates frequency of the pulses from the flow meter sensor. The
number of pulses over preset measure interval method convenient when pulsating
flow or especially noisy signals are encountered.
Reset Main Total
Value?
Press Ent key to
reset Totalizer!
The Totalizer has
been reset!
Pilot Total Mode
Disabled
PT Flow Start
10.0% FS
PT Event Volume
0.0 Gal
Reset Pilot Total
Value?
Press Ent key to
reset Totalizer!
The Totalizer has
been reset!
Opt #1 function
Disabled
Low Flow Cut–off
1.000% FS
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