Operating Manual
3KXG165002R4201_2021_04
ABB PROPRIETARY INFORMATION
64
GLA531 Series LGR-ICOS™ Gas Analyzer
Inlet Solenoid-Valve
The inlet solenoid valve is a customized direct-acting normally closed two-way solenoid valve. Its welded
stainless-steel construction eliminates the possibility of external leakage. The valve seal is PTFE.
Its control comes from the two-port solenoid driver board on the first channel.
Figure 53 Inlet Solenoid Valve Assembly
PWM Pressure Controller
The gas pressure control of the analyzer is a pulse width modulated (PWM) electronic controller which works
together with an electronic proportional control (EPC) valve.
Figure 54 PWM Pressure Controller
EPC Valve
An EPC valve is a dynamic adjustment for maintaining a target pressure inside the ICOS cell. The valve size
opening lowers the ICOS cell pressure, and the valve size closing increases the pressure. The EPC valve is
normally closed.
Figure 55 EPC Valve with a Wire Connector