RKI Instruments GX-3R User Manual

12 • Chapter 2: Description GX-3R Operator’s Manual
Control Buttons
Two control buttons, AIR and POWER MODE, are located below the LCD.
Alarm LEDs
The six alarm LEDs around the edge of the case alert you to gas, low battery, and failure
alarms.
Buzzer
One solid-state electronic buzzer is located inside the case. Sound exits the case through a
hole in the middle front of the case. The buzzer sounds for gas alarms, malfunctions, low
battery voltage, and as an indicator during use of the GX-3R’s many display and adjustment
options.
Vibrator
A vibrating motor inside the GX-3R case vibrates for gas alarms, unit malfunctions, and as an
indicator during normal use of the various modes of the GX-3R.
NOTE: If STEALTH is set to ON, the vibrator only functions when VIB in the STEALTH
Gas Select Mode item is set to ON. See “Stealth and Vibrator Settings
(STEALTH)” on page 109.
Sensors
The GX-3R uses three sensors to monitor combustible gas, oxygen (O
2
), carbon monoxide
(CO), and hydrogen sulfide (H
2
S) simultaneously. The sensors are located inside the GX-3R
and are held in their sockets by the sensor retainer and bottom cover. The sensors use different
detection principles, as described below.
Combustible Gas Sensor
The combustible gas sensor detects combustible gas in the % LEL range using a catalytic
element. The element’s resistance changes based on the reaction of gas with oxygen. The
change in resistance affects the current flowing through the element. The GX-3R’s circuitry
amplifies the current, converts the current to a gas concentration, and displays the
concentration on the LCD.
Table 3: GX-3R Control Button Functions
Button Function(s)
AIR • turns on LCD backlight
• resets alarm condition if LATCHING is set to ON in Maintenance Mode
• enters User Mode, Maintenance Mode, and Gas Select Mode when used
with POWER MODE button
• activates the demand zero function (adjusts the GX-3R’s fresh air reading)
• changes the value of a parameter available for adjustment
• scrolls through parameter options
POWER MODE • turns the GX-3R on and off
• turns on LCD backlight
• enters and scrolls through Display Mode
• enters instructions into the GX-3R’s microprocessor
• resets alarm condition if LATCHING is set to ON in Maintenance Mode
• enters User Mode, Maintenance Mode, and Gas Select Mode when used
with AIR button

RKI Instruments GX-3R Specifications

General

Brand	RKI Instruments
Model	GX-3R
Category	Measuring Instruments
Language	English