Gas Detection (Australia) Pty Ltd Page 7 of 12 M-GDA-4360-V11-Rev 3
Calibration:
Sensors are issued tested & pre-calibrated under controlled lab conditions. Changes to humidity,
temperature, and other environmental factors affect the sensor accuracy and may need a re-set of the
fresh air zero point when introduced to new environments.
The GDA 4360 is an auto calibrating device and under most cases will auto calibrate to new environment
over time
Functional testing may be carried out with a suitable test gas to ensure that the 4-20ma o/p corresponds
with the gas level. This should be undertaken when the unit is fully assembled and using a flow rate of
~0.5L/min of the target gas. Test gas and equipment are available from Gas Detection Australia.
Fresh air Zero point Calibration:
A manual fresh air zeroing (span) of the sensor can be performed when the sensor has been powered for
a minimum of one hour. The fresh air zero can be performed when the sensor is in a known fresh air. The
sensor must be in the fresh air conditions for a minimum of five minutes or until the output has reached a
stable point.
To perform a manual fresh air zero (span) point calibration:
1. Remove the GDA 4360 from the wall to access the back of the sensor unit;
2. Add a jumper to pins 1 and 3 of P3 see picture below, This enters Manual Calibration Mode (see table
for LED sequence);
3. Press and hold the SPAN/ Fresh Air Zero calibration button S1 for 1 to 2 seconds (see table for LED
sequence):
If the Fresh Air Zero was successful (see table for LED sequence)
If the Fresh Air Zero was NOT successful (see table for LED sequence). Repeat step 3
after ensuring that the sensor is in fresh air and stable.
Note: Do not press the ZERO button as it will perform a Nitrogen zero.
4. When successfully zeroed remove the Manual Calibration jumper from header P3 and return to normal
operation.
Alternate Blinking at once per
second
Alternate Blinking at once per
second for ~ 4 sec
