Guidance on the calibration interval of the O2NE+ and Safe-Ox+ devices can be found in the O2NE+ & Safe-Ox+ User Manual which is available on both the O2NE+ and Safe-Ox+ product pages in the Analox Group website..
As a rule, Analox recommends the Safe-Ox+ and O2NE+ devices are proof tested once per year (flow a challenge gas across the sensor to confirm it reads correctly). Calibration adjustment is unnecessary if your O2NE+ / Safe-Ox+ reads correctly on the proof test gas.
For best performance the monitor should be powered and allowed to warm-up for approximately 2 hours before calibration is performed. This will allow the whole instrument to stabilise at operating temperature.
In order to perform a calibration check, you will need the following equipment:
Calibration gas: with 20.9% oxygen in nitrogen for devices manufactured after 04/03/2014 older models use 24% oxygen in nitrogen.
0.5 lpm regulator: To suit the calibration gas bottle.
Flow adaptor kit: Part No: P0120-651K for devices manufactured between 09/08/2012 and 01/11/2016.
Then follow this procedure:
- Remove the flow adaptor and gasket from its protective backing (if using the P0120-651K).
- Fit the flow adaptor including its gasket (if using the P0120-651K) to the O2 sensor and connect, with tubing, to the cylinder.
- Open the regulator to allow for the flow of gas over the sensor.
- Enter 'Technician Mode' by pressing the mode switch 3 times. If entered successfully the green LED will flash off for 1.5 seconds and on for 0.5 of a second.
- Select auto calibration by pressing the mode switch 4 times. The 2 Red Alarm LED's will light up to show you are now in this mode.
- Press the mode switch 2 times to start the Auto Calibration, the Red Alarm LED's will turn off and the Green LED will continue to flash.
- Wait one minute for the instrument to adjust. When the instrument has a new calibration value, the buzzer will sound one bleep and all the LED's will be off.
- Accept this new calibration value by pressing the mode switch 2 times. The green LED will flash to show the instrument has accepted the new oxygen value.
- To return to normal operation, press the mode switch once. The LED's and buzzer will illuminate/ sound 4 times before returning to normal operation.
If during the one minute wait period, the red or yellow LED's are illuminated consult the table below:
| ALARM 1 LAMP (RED) | ALARM 2 LAMP (RED) | FAULT LAMP (YELLOW) | MEANING | ACTION |
| ON | OFF | OFF | Calibration gas is above allowable range | Ensure the calibration gas is 20.9% oxygen in nitrogen with ±2% tolerance. |
| OFF | ON | OFF | Calibration gas is below allowable range | Ensure the calibration gas is 20.9% oxygen in nitrogen with ±2% tolerance |
| OFF | OFF | ON | Internal fault | Contact Analox |
For a brief demonstration of the calibration process, please watch the video below:
O2NE - 4. Calibration from Analox.