Crowcon Tetra User Manual

1. When the gas level returns to normal, press the operator button. This
will reset your Tetra unit to normal Run mode. If gas levels are still in
alarm, the button will have no effect.
3. Switch off unit and storage
Switching off unit
1. Press and hold the button for 5 seconds. The shut down menu
appears, continue to hold button until the unit counts down to shut
off.
Storing conditions
In order to optimize sensor performance and lifetime, your Tetra unit should
be stored in a safe, non-hazardous area, 0-30°C, 10-90%RH.
4. Additional information
For battery recharging information go to section III.
For fixing accessories go to section V.
For sampling section go to section VI.
For calibration information go to section VII.
For troubleshooting guide go to section XII.
5
Tetra Switching off
1 2
CH4 %LEL CO ppm
H2S ppm
O2 %
0.0
0.0
0
20.8
OK
OFF IN
4 sec
For any one gas, there are
normally two alarm
thresholds. These are
indicated by the alarm
icons shown.
The Tetra alarm is set to latch by default.
The unit will still continue in alarm mode
even when gas levels return to normal,
until the alarm is cleared, by pressing the
operator button.

Crowcon Tetra Specifications

General

Operating Temperature	-20°C to +50°C
Type	Portable Gas Detector
Gases Detected	Oxygen, Carbon Monoxide, Hydrogen Sulfide
Display	LCD
Ingress Protection	IP65
Sensor Types	Electrochemical