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AZ instruments optical meter for dissolved oxygen

The batteries are installed, and the device is factory-calibrated, so it’s ready for you to use!

  • Remove the storage cap (with the sponge insert) and swap it for the cage-style cap.
  • Power on. Lower the device to the desired depth (at least 15 cm below surface level), avoiding plants and algae.
  • Record your reading after 60 seconds (once temperature has stabilized).
  • Power off. Remove the cage cap. Blot the probe surface with the cloth and attach the storage cap.

Troubleshooting

  • If you’ve entered a mode from which you cannot ‘esc’, turn off the power and turn it on again. If this doesn’t resolve your issue, remove and then reinstall the batteries.
  • Ensure the probe connections are dry and tight.
  • If the storage foam has dried out, add distilled water and rehydrate the membrane for 2 hours. Then, follow the calibration check instructions.
  • If you use this in salt or polluted water, rinse thoroughly with distilled water after using. Do not expose to chlorine!

Calibration check

Optical probes don’t need to be calibrated in the same way as traditional dissolved oxygen probes. Rehydrate your storage cap once a month, especially if it’s dried out or if the meter has been exposed to chemicals. To check its calibration:

  • Clean and rehydrate the storage cap.
  • Blot the probe membrane until it’s dry.
  • Reattach the storage cap.
  • Place the probe vertically on a surface (such as a desk) for one hour.
  • Power on the meter and look for a reading between 95% and 105%. If the reading is within this range, your device is calibrated. If not, follow the calibration instructions found in the online guide.

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