HP 5973 MSD Hardware Manual page 73

Schematic of CI flow
control module
Flow module state diagram:
Result Gas A flows
Control panel lights (LEDs)
Gas A (green) On
Gas B (amber) Off
Purge (red) Off
Gas Off (red) Off
Valve state
Valve A Open
Valve B Closed
On → setpoint
MFC
Isolation valve Open
Gas A
(Methane)
supply
Gas select
valve A
Gas select
valve B
Gas B
(Other gas)
supply
Gas B flows Purge
with Gas A
Off On
On Off
Off On
Off Off
Closed Open
Open Closed
On → setpoint On → 100%
Open Open
Green
light
Mass
Flow
Controller
Calibration
valve
Amber
light
Restrictor
PFDTD
vial
Purge
with Gas B
Off
On
On
Off
Closed
Open
On → 100%
Open
 Troubleshooting
$LU OHDNV
CI ion
source
Isolation
valve
EI/CI
GC/MSD
interface
GC column
Pump out Standby, vented,
flow module or EI mode
Off Off
Off Off
On Off
On On
Closed Closed
Closed Closed
On → 100%
Off (→0%)
Open Closed
73