HP 5973 MSD Hardware Manual page 18

 Hardware Reference
5HDJHQW JDV IORZ FRQWURO PRGXOH
Gas A
(Methane)
supply
Gas select
valve A
Gas select
valve B
Gas B
(Other gas)
supply
Reagent gas flow control module schematic
When you turn off one gas and turn on the other, the system sets a 6-minute delay
with
Gas Off
selected reagent gas will flash, indicating the delay timer is active. Once the delay
is finished, the
will stop flashing and stay on.
When the MSD is turned off, all valves are closed, and all lights are off. At startup,
all valves are closed and all lights are off, except
The flow control board remembers the flow setting for each gas. When either gas is
selected, the control board automatically sets the same flow that was used for that
18
Green
light
Mass
Flow
Controller
Calibration
Amber
light
and both on to pump out the flow control module. The light for the
Purge
and lights will turn off, and the light for the selected gas
Purge Gas Off
Isolation
valve
valve
Restrictor
PFDTD
vial
.
Gas Off
CI ion
source
EI/CI
GC/MSD
interface
GC column