Teledyne GFC-7001T - Trace CO Analyzer - Manual (Page 306)

Theory of Operation Teledyne API – Model T300/T300M CO Analyzer
Teledyne Analytical Instruments 306
13.4.4.3. ZERO/SPAN VALVE OPTIONS
Any zero/span/shutoff valve options installed in the analyzer are controlled by a set of
electronic switches located on the relay board. These switches, under CPU control,
supply the +12VDC needed to activate each valve’s solenoid.
13.4.4.4. IR SOURCE
The relay board supplies a constant 11.5VDC to the IR Source. Under normal operation
the IR source is always on.
13.4.4.5. STATUS LEDS
Eight LEDs are located on the analyzer’s relay board to show the current status on the
various control functions performed by the relay board. They are listed on Table 13-4.
Table 13-4: Relay Board Status LEDs
LED COLOR FUNCTION STATUS WHEN LIT STATUS WHEN UNLIT
D1 RED Watch Dog Circuit
Cycles On/Off every 3 seconds under direct control of the analyzer’s
CPU.
D2 YELLOW Wheel Heater HEATING NOT HEATING
D3 YELLOW Bench Heater HEATING NOT HEATING
D4 YELLOW Spare N/A N/A
D5 GREEN
Sample/Cal Gas Valve
Option
Valve Open to CAL GAS FLOW Valve Open to SAMPLE Gas Flow
D6 GREEN Zero/Span Gas Valve Option Valve Open to SPAN GAS FLOW Valve Open to ZERO GAS FLOW
D7 GREEN Shutoff Valve Option Valve Open to CAL GAS FLOW
Valve CLOSED to CAL GAS
FLOW
D8 GREEN IR SOURCE Source ON Source OFF