# Instrument adjustment

Tap and select Instrument / Adjust to perform instrument adjustments. The procedures available in the Adjust screen depend on the connected instrument.

The Adjust screen is not available during a survey. End the current survey to perform an instrument adjustment.

Trimble recommends carrying out instrument adjustment tests in the following situations:

- Whenever the instrument may have been roughly handled during transport.
- When the ambient temperature differs by more than 10°C (18°F) from the previous collimation test.
- Immediately prior to high precision angle measurements in one face.

This help provides instructions for performing the tests using the Trimble Access software running on the controller. Depending on the instrument, you may also be able to perform these tests through the face 2 menu display. For more information, refer to the documentation for your instrument.