C) SETTING THE LAG TIME
IMPORTANT: For best results with Compound Loop
Control systems, the lag time should be measured when
the water is at its AVERAGE daily flow rate.
1
) Press ESC (escape) to exit the Control Parameters and
return to the Main Operating Screen.
If the SMARTVALVE is configured for COMPOUND
LOOP CONTROL, the TOP LINE will display the water
FLOW rate and also indicate if the valve is set for automatic
(AUTO) or manual (MANL) operation. Press the select
(
SEL) keypad button, then press RES (residual) to
display the residual reading (PPM) in place of the water
flow reading. Also, if it is set for AUTO operation, press
SEL a second time, then press MANL (manual).
OR
If the SMARTVALVE is configured for RESIDUAL ONLY
CONTROL, the TOP LINE will display the residual (RES)
level in PPM (parts per million) and indicate if the valve
is set for automatic (AUTO) or manual (MANL) operation.
If set for AUTO, press the MENU button, then press
MANL (manual).
2) Based upon the Residual Range (RES RANGE) that
was set in the Configuration Mode, a residual level Set
Point (SP) must be established. Press the SEL (select)
button, then press the MENU button. Press SP (set
point), scroll UP or DOWN to the preferred set point
value, then press ENT (enter) to accept. Finally, press
ESC (escape) to return to the main operating screen.
3) The next step is to “balance” the system by manually
adjusting the gas feed rate until the displayed residual
reading matches the residual SET POINT value. Start
by pressing the VALVE button. Then use the OPEN and
CLOSE buttons to gradually adjust the system into
balance. NOTE:
This process may take a significant
amount of time, depending on the size of the system.
4) For Residual Only Control systems, proceed to step
No. 5. HOWEVER, for Compound Loop Control systems,
the water FLOW rate must also be recorded prior to
proceeding to the next step. To do so, press the MENU
button, then press FLOW and the water level will be
displayed in the selected Flow Units. Record the level.
Then press MENU a second time and press RES to
display the residual reading again. Proceed IMMEDIATELY
to step 5.
5) While observing the displayed residual reading, “upset”
the system by manually increasing or decreasing the gas
feed rate by a substantial amount while simultaneously
starting an accurate timing using a stop watch.
6) Closely observe the residual reading on the screen until
it begins to reflect the upset condition. At that point,
immediately record the timed value in seconds. Once
recorded, manually adjust the gas feed rate again to get
the system back into balance.
7) Once the system is in balance, press and hold the No. 1
keypad button to access the Control Parameters again.
F
or Residual Only Control. ENTER the recorded time as
the FIXED LAG TIME. For Compound Loop Control,
ENTER the recorded time as the VARIABLE LAG TIME.
8) Finally, for Compound Loop Control, proceed to the
FLOW @ VAR LAG parameter and ENTER the previously
recorded water flow rate. NOTE:
Also, check the current
water flow rate to make sure it has not varied much (+/- 5%)
during the timing process. If so, the process must be
r
epeated.
NOTE:
Relocation of the sample point to achieve accurate
results is not uncommon and may require significant
time and trial.
Once all control parameters have been set and
produce the necessary results, proceed to section
8.0 (OPERATIONAL MODE).
NOTE:
At this time, it is also recommended to
re-enter the configuration mode and lock the control
parameters to prevent unauthorized access.
Each of the four Control Schemes available for the Model 7009
and 7010 SMARTVALVES has separate OPERATIONAL
MODE PARAMETERS and settings which are explained
below. These parameters may be changed by the operator at
any time, regardless if the valve is set in the MANL (manual) or
AUTO (automatic) operational mode. The currently active
mode (AUTO or MANL) will always be indicated on the far
right, TOP LINE of the display.
To change the operational mode, simply press the MENU or
SEL (select) button. ONLY the mode which is not in use will be
shown on the BOTTOM LINE of the display. Press the keypad
button (No. 3) of the displayed mode to make the change. The
main operating screen will now show the selected mode on the
TOP LINE.
IMPORTANT:
When the valve is set in the manual (MANL)
operational mode, the gas feed rate may be adjusted in one of
the four following ways, depending upon the condition.
1) Fully Electric – In the event of loss of the analog input
signal(s), use the keypad buttons and the digital display.
Simply press the VALVE button. Then use the OPEN and
CLOSE buttons to adjust the gas feed rate accordingly.
2) Electric Manual – If the remote meter assembly is
temporarily out of service, use the thumbwheel and
digital display. IMPORTANT:
To avoid gear damage
and possibly upset the electrical zero setting, it is
ESSENTIAL to place the valve in MANL operation
PRIOR to turning the thumbwheel. Also, be sure to
bypass the remote meter assembly by connecting the
vacuum tubing from the vacuum regulator directly to the
SMARTVALVE inlet fitting.
3) Manual – In the event of power loss, use the thumb-
wheel and remote metering tube. To adjust the feed rate,
simply turn the thumbwheel while using the remote
meter ball float as a guide.
15
8.0 OPERATIONAL MODE
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