Alicat V Series Volumetric Flow Meter User Manual
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V Series Volumetric Flow Meter Operation
The V Series can have several screen “modes” depending on how the device is ordered. All V Series
meters have a default Main Mode, Select Menu Mode, a Gas Select Mode (the Gas Select Mode
may not be available on meters calibrated for a custom gas or blend), a Communication Select Mode,
Manufacturer Data Mode and a Miscellaneous Mode. In addition, your device may have been ordered
with the optional Totalizing Mode (page 38). The device defaults to Main Mode as soon as power
is applied to the meter. Note that volumetric meters are intended for use in near atmospheric
conditions (Please see page 28).
Main Mode
The main mode screen shows the volumetric flow in the units specified at time of order. In the flow
mode, only two buttons are active as shown in Figure 12. The process gas that is selected is shown
directly under the flow units.
Tare
Volume
CCM
Air
+0.000
Volume Main
Figure 12. Main Mode Display, V Series Flow Meter
The “MODE” button in the lower right hand corner toggles the display between the Main Display and
the Menu Display.
Tare – Pushing the dynamically labeled “Tare” button in the upper right hand corner tares the flow meter
and provides it with a reference point for zero flow. This is a simple but important step in obtaining
accurate measurements. It is good practice to “zero” the flow meter each time it is powered up and
whenever a known zero flow condition exists. If the flow reading varies significantly from zero after an
initial tare, give the unit a minute or so to warm up and re-zero it.
Zeroing the unit while there is any flow will directly affect the accuracy by providing a false zero point.
If in doubt about whether a zero flow condition exists, remove the unit from the line and positively block
both ports before pressing the “Tare” button. If the unit reads a significant negative value when removed
from the line and blocked, it is a good indication that it was given a false zero. It is better to zero the
unit at atmospheric pressure and a confirmed “no flow” condition than to give it a false zero under line
pressure.
Note: A remote tare can be achieved by momentarily grounding pin 4 to tare as shown in Figure 5 on
page 9.