Gas A
(methane)
supply
Gas B
(other)
supply
Figure 42
Reagent gas flow control module schematic
Table 13
Flow control module state diagram
Result
Gas A flow
Gas A
Open
Gas B
Closed
MFC
On
setpoint
Shutoff valve
Open
The Open and Closed states are shown in the monitors as Open and Closed
respectively.
5977B Series MSD Operating Manual
Gas A
select valve
Gas B
select valve
Purge
Gas B flow
with Gas A
Closed
Open
Open
Closed
On
setpoint
On
Open
Open
MFC
Calibration
valve
Restrictor
Calibration
vial
Purge
with Gas B
Closed
Open
100%
On
100%
Open
Operating in CI Mode
Shutoff
valve
GC/MSD
interface
GC column
Standby, vented, or
Pump out
flow module
EI mode
Closed
Closed
Closed
Closed
On
100%
Off
0%
Open
Closed
5
CI
source
129