Operating Manual
3KXG165002R4201_2021_04
ABB PROPRIETARY INFORMATION
57
GLA531 Series LGR-ICOS™ Gas Analyzer
Figure 45 DC-to-DC Voltage Converter Board
Temperature Controller
Depending on the selected options, up to four temperature controllers are inside the analyzer (see Figure 46
below). Each temperature controller receives a K-Type thermocouple (T/C) input. It has a single voltage output to
control a DC solid-state relay as shown in Figure 47.
Figure 46 Temperature Controller
DC Solid-State Relay
DC solid-state relays (SSR) inside the ICOS Module switch the heaters on and off, and turn on the exhaust
pump. The SSR for the heaters receive their enable/disable commands from the temperature controllers. The
SSR for the exhaust pump receives the control signal from the two-port solenoid driver on channel 2. When an
SSR is enabled (energized), the green LED on top illuminates.