946 Controller Instruction Manual
pg. 47
6.7 Channel Setup for Flow Measurement and MFC Based Pressure
Control
When an MFC module is installed, the 946 Controller can operate MKS Mass Flow Controllers to control
the mass flow rate or operate a mass flow meter to monitor the mass flow rate. Up to six MFCs can be
simultaneously operated by one 946. When both MFC and pressure (CM, PR, CC, HC) modules are
installed, the pressure and flow can dynamically be controlled.
Figure 6-12 946 Front Panel.
6.7.1 Simple Operation of a Mass Flow Controller
An MFC can set to Open, Closed or Set Point from the front panel.
•
Open: To set an MFC with integral control valve to fully open:
o
Move the green LED on the front panel to the desired MFC channel by pressing either
the
or the
key;
o
Press the
Open
key, and an “Open” will appear in the display line for the selected channel
on the front panel and start blinking;
o
Press
Enter
key to confirm the operation, and the “Open” indicator will stop blinking.
When an MFC is set to Open mode, the flow rate is often significantly higher than
the full-scale flow rate of the mass flow controller and is too high to be measured by MFC.
In this situation, the display would Indicate “ > [110% of the f.s. flow rate]”, for
example >1100 for a 1000 SCCM MFC.
•
Close: To set an MFC to fully closed:
o
Move the green LED on the front panel to the desired MFC channel by pressing either
the
or the
key
o
Press the
Close
key, and “Close” will appear and start blinking in the display line for the
selected channel
o
Press
Enter
key to confirm the operation, and the “Close” indicator will stop blinking.
•
Setpoint: to flow gas at the rate specified by the MFC’s set point::
o
Move the green LED on the front panel to the desired MFC channel by pressing either
the
or the
key;
o
Press the
Setpoint
key, and “SP” and flow set point value will be displayed alternatively in the
display line for the selected channel.
o
Press
Enter
key to confirm the operation and the “SP” indicator will change to black and
remain on.