15
MAIN
The following parameters are displayed in the
Main
mode: Pressure; Temperature; Setpoint;
Volumetric Flow and Mass Flow.
This
mode defaults on power up, with mass
flow as the primary displayed parameter.
Pressing the button next to the parameter will
put that parameter in the primary display.
Press the button a second time to change the
engineering unit associated with the device
display (button units) and / or the data feed
(device units). See page 16.
Gas Pressure: This sensor references hard
vacuum and reads incoming pressure both
above and below local atmospheric pressure. This parameter is moved to the
primary display by pushing the button above
PSIA
. Pushing this button again will
allow you to show Absolute Pressure, Gauge Pressure or Barometric Pressure in
devices that have a barometer.
Gas Temperature: MC-Series flow controllers measure the incoming temperature
of the gas flow. The temperature is displayed in degrees Celsius (°C). This
parameter is moved to the primary display by pushing the button above
°C
.
Pushing the button again allows you to
select 0C (Celsius), K (Kelvin), 0F
(Fahrenheit) or 0R (Rankine) for the temperature scale.
Setpoint
: The setpoint (
SETPT
) is shown in the upper right of the display.
For information on changing the setpoint see SETPT SOURCE, page 18.
Volumetric Flow Rate: This parameter is located in the lower left of the display.
It is moved to the primary display by pushing the button below
CCM
in this
example. Your display may show a different unit of measure. Pushing this button
again will access a list of selectable engineering units.
Mass Flow Rate: The mass flow rate is the volumetric flow rate corrected to a
standard temperature and pressure (typically 14.696 psia and 25 °C).
This parameter is located in the lower middle of the display. It can be moved to
the primary display by pushing the button below
SCCM
in this example. Your
display may show a different unit of measure preceded by the letter
S,
N
or a
True
Mass Unit
. Pushing this button will access a list of selectable engineering units.
To get an accurate volumetric or mass flow rate, the gas being measured
must be selected. See Gas Select, page 24.
Mass flow in units preceded by an S or N is impacted by the STP / NTP. See page 28.
MENU: Pressing
MENU
switches the screen to the
Select Menu
display.
#C
+21.50
+0.00
CCM
TOTAL/
MENU
SETPT
+0.00
SCCM
Air
PSIA
+13.60
+0.00
SCCM
+0.00
When using a mass flow controller as an absolute pressure
controller, the mass flow rate may momentarily exceed the flow
measurement capability (full scale + 28%) of the unit. This may
occur when the unit is asked to make an abrupt pressure change.
If the optional totalizer is in use at that time, the totalized value will
necessarily become incorrect and a TMF error status will be displayed.
Please reset the totalizer if such an ‘over-flow’ condition has occurred.
Mass Flow
