2.2 Device Hardware Interfaces

Instrument operation is dialog driven from the display with the aid of the three function buttons (see FIGURE 2-1)

2.2.1 Button Definitions

BUTTON	DESCRIPTION
	The Button is used to turn instrument ON or OFF and to confirm user action selections. When the ▲ button and the button are pressed simultaneously at instrument start-up, the Options Setup mode displays.
	The ▼ Button is used to page down through data screens in measuring mode or as a page back and to decrease the values in Setup mode. Holding this button for 3 seconds while in Normal Measure mode activates the InstantAlertTM alarm.
	The ▲ button is used to reset peak, STEL TWA and acknowledge alarms (where possible) or access calibration in Measuring mode. It is also used as page up or to increase the values in Setup mode.

2.2.2 LED Definitions

LED	DESCRIPTION
GREEN	The Safe LED flashes once every 15 seconds to notify the user that the instrument is ON and operating under the conditions defined in Section 3.7. This option can be turned OFF through the MSA Link software
RED	The Alarm LEDs are visual indications of an alarm condition or any type of error in the instrument
YELLOW	The yellow LED is a visual indication of an instrument fault condition. This LED turns ON with the following conditions: Instrument memory error Sensor Missing Sensor Error
RED / GREEN	The Charge LED is a visual indication of charge status. Red indicates the instrument is charging Green indicates the charge is complete

2.2.3 Vibrating Alarm

The instrument is equipped with a vibrating alarm.

2.2.4 Backlight

The backlight automatically activates when any front panel button is pressed and remains ON for the duration of user-selected timeout. This ON/OFF duration can be changed through MSA Link software.

2.2.5 Horn

The horn provides an audible alarm.

2.2.6 On-Screen Indicators

Graphic Symbols
Gas Type
Gas Concentration

Alarm Symbol