CALIBRATION
Zero Calibration
The zero calibration can be set by covering the sensor to ensure no air flow and
pressing the zero button for 3 seconds. If either the remote or local LCD is present, the
display will read
ZEro
and then sequence back to the home display.
SPAN Calibration
The span calibration can be adjusted only after setting the zero adjustment. It must
be completed within 5 minutes of the last zero calibration. The span calibration button
will be ignored until the zero calibration is completed. Place the sensor in airflow that
matches the maximum selected range of the transmitter. Press and hold the span
button for 3 seconds. If either the remote or local LCD is present, the display will read
SPAn
and then sequence back to the home display. If the span calibration is attempted
before adjusting the zero calibration, the
FAiL
error message will be displayed briefly
before returning to the home display.
LCD Display
The Series AVLV can be ordered with an optional, integral LCD. It comes with a
housing cover and overlay to protect the display. The display will plug into the pins as
shown in Figure 5. If the display is not needed for normal operation, the transmitter can
be ordered without the LCD.
Another option for models that do not have a display would be to use a Model A-435-A
remote display tool which can plug into the connector shown in Figure 6. The remote
display tool has two buttons that function identically to the buttons on the PCB.
Display Error Messages
ovEr
= The air velocity is greater than the maximum span value causing an Over
Range Error
UndEr
= The air velocity is less than the minimum span value causing an Under Range
Error
FAiL
= When the span or zero buttons are pressed, the air velocity value is out of the
range to allow a correct setting. This may be due to a sensor failure.
Err1
= The sensor is damaged.
PROGRAMMING MENUS
Home Menu
During normal operation, the display will be in the Home Menu and will display the
current measured pressure and the engineering units.
Menu Access Security
While in the Home Menu, press and hold the Zero and Span buttons simultaneously
until
SECUr
appears on the display in order to access the other programming menus.
Upon releasing the buttons, the display will indicate the current security level.
If the current security level is the security level desired (i.e. Security Level 0), press
and hold the span button for 3 seconds to enter the Velocity or Air Flow Menu.
If the security level is not the desired level, the security level can be changed
temporarily to a lower security level or permanently to a higher level of security by
pressing the zero button. A security code will appear on the display, and it can be
changed to one of the codes listed in Table 3. The span button chooses which digit
and the zero button increments the value of that digit. Pressing and holding the span
button will store the value.
The level of access to the programming menus and the calibration is limited based on
the security level. Table 3 details the level of access for each security level.
Figure 5: Pluggable display diagram
Figure 6: Remote display diagram
SW1
SPAN
ZERO
PWR GN
D
IOUT VOUT
D1(+
)
D0(-) CO
M
SW1
SPAN
ZERO
PWR
GN
D
IOUT
VOUT
D1(+
)
D0(-)
CO
M
There is a 5 second delay from the time the zero or span calibration
buttons are released until the time that the change in calibration
takes place. This delay is used to reduce vibration or disturbances of the user related
to the button presses.
The security level that is set in the Programming Menu section
of the manual will determine which calibrations, if any, may be
adjusted by the user.
NOTICE
NOTICE
