
PlasmaQuant MS Series
Gas
Control System
41
The unit will provide false flow-control if the gas-flow path becomes contaminated
with air.
The flow sensor consists of a heated element and two temperature sensors; one before
and one after the heated element. When gas flows past the heated element, the
sensors measure the temperature and calculates the mass flow based on the
temperature differential that is measured.
5.2
Theory of Operation
5.2.1
Instrument Gas Control
The sample introduction PCB interfaces with the system control PCB, with a 40-way
ribbon cable, and controls the following gas box items:
Figure 5-9 - Connection of Sample Introduction PCB to System Control PCB
Argon pressure switch
Instrument gas supply solenoid
Auxiliary and plasma gas solenoids
Gate and small isolation valve solenoids
Igniter assembly
The system control PCB directly controls the following gas box items:
Nebulizer gas mass flow controller (MFC1)
Sheath gas mass flow controller (MFC2)
Nitrox gas mass flow controller (MFC3)