2021.08.19
•
REV. 1
• MASS FLOW METER OPERATING MANUAL
7
Device Ports
Your meter has been shipped with plastic plugs fitted into its ports. To decrease the chance
of contaminating the flow stream, do not remove these plugs until you are ready to install
the device.
Standard gas flow meters have female inlet and outlet ports. VCR®-compatible and other
specialty fittings may have male connections.
•
If you are using a fitting that does not have a face seal, use thread-sealing Teflon tape to
prevent leakage around the port threads, but do not wrap the first two threads entering
the device. This will minimize the possibility of getting tape into the flow stream and
clogging the laminar flow elements.
•
Face seal fittings do not need Teflon tape applied to the threads.
!
Warning:
It is not recommended to use pipe dopes or sealants on the process connections
as these compounds can cause permanent damage to the meter should they get into
the flow stream.
Connecting Your Gas Flow Meter
Your flow meter can measure flow generated by positive pressure and/or suction. Connect
the meter so that the flow travels in the same direction as the flow arrow, usually from left
to right from the front of the device.
!
Warning:
Using the flow meter above the maximum specified common mode or differential
pressure will result in permanent damage to the internal pressure sensors.
A common cause of this problem is the instantaneous application of high-pressure gas,
as from a snap-acting solenoid valve either upstream or downstream of the flow meter.
If you suspect that your pressure sensor is damaged, please discontinue use of the
device and contact support (
page 12
). See the chart below for pressure limits.
Model
Maximum Common
Mode Pressure
Maximum Differential
Pressure
Standard meters
175 psia
75 psid
Low-pressure-drop meters
80 psia
10 psid
High-pressure meters
400 psia
75 psid
A mass flow meter with male
VCR
®
-compatible connections.
A mass flow meter’s basic
process connections.
A mass flow meter with male
VCO
®
-compatible connections.
Inlet
Connection
Outlet
Connection
Flow Direction Indicator
