Replacing AQT400 base module - AQT400

AQT400 Series Configuration Guide

Document code
Document type
User guide
  • 3-mm Allen key
  • Crosshead screwdriver
  • Laptop with standard terminal program
  • Service cable kit
Order the AQT400 base module (product code AQT400U-SP, AQT400T-SP, and AQT400I-SP) from Vaisala.
Replace the AQT400 base module when the device health (service indicator) of your AQT400 is lower than 30 %.
CAUTION To avoid damaging the device, carry out the replacement indoors.
  1. If you have configured your AQT400 before and want to maintain the configurations, save the parameters before you detach the old base module. They are not automatically transferred when you change the base module.
  2. Remove AQT400 from the mounting bracket at the installation site.
  3. Remove the radiation shield.
  4. Remove the 8 screws that hold the lid in place.
  5. Lift the lid so that you can see the lid connector. Unplug the connector from the circuit board of the base module.
  6. Take the new calibrated base module from the box.
  7. Plug the connector to the circuit board of the new base module, check that the O-ring is in place, and close the lid.
  8. Attach the screws tightly. Tightening torque 0.8 Nm.
  9. Attach the radiation shield with the 3 screws and tighten the screws.
  10. Verify the AQT400 base module installation.

    With the default settings, the spare part is fully compatible with AQT400. If you saved your previous configurations, set them now to the new base.

  11. Verify that the real-time clock is correct and adjust it, if required:
    • In AQ Tool, select Set to UTC.
    • In a terminal program, use the date command: date [YYYY-MM-DDTHH:II:SS].

      For example:

      date 2017-05-22T12:34:11
When AQT400 is switched on, let the unit stabilize for at least 24 hours before using the measurement results. To ensure optimal measuring accuracy, Vaisala recommends a 48-hour stabilization period. The units take measurements during the stabilization period, but they are marked as invalid.
The base module is electronic waste. Follow local requirements when disposing of the product.