Scott QuadScan II 7400, Operation & Maintenance Manual, Page: 15 / 121

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Display/Function Assembly
The individual visual display of absolute value of the gas concentrations, alarm status, and channel status for all
active channels provides the status of the gas/flame detection system.
Operator intervention and/or automatic alarm corrections can be made from the information displayed by this unit.
Gas Concentration is displayed on a LCD in units of PPM, PPB, % and none (flame applications) in any combination
of the four.
Individual Channel Status is displayed by a 2 color LED for each active channel:
Channel OK Green
Current Loop Fault Flashing yellow (flashing until the reset button is pressed, and then it becomes solid
yellow).
Channel Inhibited Flashing yellow/green (an inhibited channel cannot be set to steady color)
Individual alarm statuses are displayed for warn and alarm events by a yellow (warn) and red (alarm) colored LED for
each active channel. The individual alarm LEDs flash when an alarm condition is detected and remain flashing until
acknowledged by the reset button.
The function section of the unit is used for all programming and setup requirements. Five tactile feel switches are
provided to implement the following functions:
SETUP To activate programming entry to the system. This also moves the alphanumeric selection one position to
the right on the LCD each time the switch is activated.
UP To scroll up through the various channels or programming options
.
DOWN To scroll down through the various channels or programming options.
ENTER To enter the required programmed option selected from the UP or DOWN switches.
ESCAPE To return to a previous menu or selection each time the switch is activated. This will
eventually return to the gas concentration display.